yashsingh1/xdaforums huggingface dataset:
[OnePlus 8T Guides, News, & Discussion] neopbm:
Thanks, i'll see if i try that as my goal is not to have root or TWRP. Just 100% stock with older version than 11.0.12.12
[OnePlus 8T Guides, News, & Discussion] BillGoss:
In that case just use MSM Tool and then install the full version that you want to end up on. That's a lot simpler as you're not trying to keep TWRP or root.
[OnePlus 8T Guides, News, & Discussion] neopbm:
Saddly if i am correct, that tool only exit for Windows. And i dont have any Windows computer.

So will wait and see if next update fix my os crashing issue. As i am not sure that it is safe to use the restore zip.

Thanks for the time spent !!
[OnePlus 8T Guides, News, & Discussion] BillGoss:
One last point. If no MSM Tool, then use TWRP to flash the rom you want, format data and reboot. That will bring you up on a clean, unrooted, no TWRP system.
[OnePlus 8T Guides, News, & Discussion] Some_Random_Username:
Added OOS 11.0.12.12 (EU) and 11.0.11.11 (India) to OP
[OnePlus 8T Guides, News, & Discussion] vancouverp:
Is the Global variant full zip still not available? Does it usually take this long for OnePlus to release it? I must be missing something.
[OnePlus 8T Guides, News, & Discussion] BillGoss:
I've seen it take nearly 2 months before the full zip becomes available for AA.
[OnePlus 8T Guides, News, & Discussion] spigolon97:
Is latest beta based on Android 12?
[OnePlus 8T Guides, News, & Discussion] DjBastard:
Hi

Please upload Rom KB05AA International

Oxygen OS 11.0.12.12.KB05AA

Greattings
[OnePlus 8T Guides, News, & Discussion] BillGoss:
Please provide link to full rom then the OP can upload it. :)
[OnePlus 8T Guides, News, & Discussion] osm0sis:
Edit: Wrong thread 😅
[OnePlus 8T Guides, News, & Discussion] GraveDigger176:
Is out on the OnePlus site
[OnePlus 8T Guides, News, & Discussion] Some_Random_Username:
Added OOS 11.0.12.12 (global) to OP.
[OnePlus 8T Guides, News, & Discussion] VexterDex:
Thank you for the constant updates, this is super helpful for us tinkerers 💯💯
[OnePlus 8T Guides, News, & Discussion] dlb4all:
The OOS 11.0.13.13 (global) delta update just rolled for my device . its 122 MB . ill try Charles proxy to capture the link.
[OnePlus 8T Guides, News, & Discussion] Some_Random_Username:
Added OOS 11.0.11.11 (India) to OP, along with OxygenOS 12 Open Beta 1 and associated downgrade zips.
[OnePlus 8T Guides, News, & Discussion] ivanperezcaro:
OxygenOS 11.0.13.13.KB05BA (EU)

OnePlus8TOxygen_15.E.31_OTA_0310_all_2202182356_c7bd2.zip

MD5: ecc4bccb555141973baf8cfb28a4ad04

[Updated] Android Security Patch to 2022.02
[OnePlus 8T Guides, News, & Discussion] shadowstep:
Added OOS 11.0.13.13 (EU) to the OP.
[OnePlus 8T Guides, News, & Discussion] JimDandy68:
Is this the correct link for global, 11.0.13.13.KB05AA? I found it in a logcat when upgrading, and I can download the zip, but not sure how to verify.
[OnePlus 8T Guides, News, & Discussion] Rootk1t:
it was already posted https://xdaforums.com/t/updates-thread.4188149/post-86470975
[OnePlus 8T Guides, News, & Discussion] JimDandy68:
Apologies, I was just looking at this last page of the thread.
[OnePlus 8T Guides, News, & Discussion] shadowofdeth:
Can the downgrades be flashed on a device with a custom recovery without issue?
[OnePlus 8T Guides, News, & Discussion] shadowstep:
Added OOS 11.0.13.13 (Global) to the OP.
[OnePlus 8T Guides, News, & Discussion] Yash1213:
Hi guys, I am on Evox A12 right now. I desperately need to go back to STOCK ROM (any A11 version). None of the TWRPs let me flash the official updates saying there's an error. However, I haven't tried the downgrade ones mentioned in this post. I just want to confirm are these zips TWRP flashable since I have a Mac and it's very hard for me to run a .bat file. ANY URGENT REPLY WOULD BE HEAVILY APPRECIATED. Thank you so much in advance.
[OnePlus 8T Guides, News, & Discussion] azoller1:
Yes these zips should work ok in TWRP, but may not work on some a12 ROMs due to decryption issues. I don't know if Evox is decrypted or not. You can try using fastboot instead to revert back to OOS. Check out the guide in this forum.
[OnePlus 8T Guides, News, & Discussion] sansanc:
Well, you can also install some Windows on virtualbox. And then configure VB to pass the USB port to that Windows.
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
Can one install Windows for free? Sorry to ask, I do not run Windows or MacOSX (only Linux).
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
Just curious: Have you also tried to adb sideload from, say, latest twrp 3.6.1 image booted from fastboot?
[OnePlus 8T Guides, News, & Discussion] sansanc:
Just get 7 or even xp from torrents. Just for connecting your phone, is more than enough. Or you can use linux as well. There's adb for it.
[OnePlus 8T Guides, News, & Discussion] Gameplayraja:
How do i use the 11.0.13.13: OnePlus8TOxygen_15.O.31_GLO_0310_2202182359 paylod.bin to restore my oneplus 8t after failing to root it and now being stuck in a boot loop.
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
@sansanc : for all I know several hard un-brick methods do require windows. That is not a problem for me : I easily find someone (majority almost :) ) with a windows computer ... but: do you know any android phone one can hard un-brick without windows? adb will of course not help. Because adb won't work hard brick-ed ... even fastboot does not work hard brick-ed!
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
can you still get into fastboot, recovery or fastbootd?
[OnePlus 8T Guides, News, & Discussion] sansanc:
Fortunately i never had to unbrick a phone. So i don't know. I just mentioned linux as an alternative solution for adb. But most serious utilities are on windows, yeah.
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
We all read OOS 12 NA and IN (not yet EU) are rolled out. Did anyone upgrade yet? I wonder: did partitions (amount and block device names) remain or did they change from 11 to 12? In case names remained, did sizes stay the same as well? I did not find a full zip yet to figure out myself.
[OnePlus 8T Guides, News, & Discussion] xstefen:
parts changed massively, install the open beta test zip then the incremental. im attempting to piece together a full zip right now
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
Thanks, I run latest PE A12 (with latest EU OOS A11 firmware partitions) on both slots and was wondering if somehow it will make sense or will be possible to flash upcoming EU OOS A12 firmware partitions on top of PE A12. If I understand you, such may not be the case? I'll ask the specific firmware partitions question again on the PE A12 thread once EU OOS 12 is available.
[OnePlus 8T Guides, News, & Discussion] shadowstep:
Added KB2001_11.C.11 (IN) to the first post.
[OnePlus 8T Guides, News, & Discussion] xstefen:
it wont do any good, likely cause breakage. until 1+ releases A12 kernel source its gonna be A11 firmware on all customs
[OnePlus 8T Guides, News, & Discussion] IAMAB:
The fingerprint scanner is completely broken on my OnePlus 8t IN post A12 upgrade. Followed the usual upgrade method(Install from local storage, followed by Magisk Install(install to inactive slot). What should I do now?

Deleted all previous fingerprints, tried to add a new but no luck. The scanner doesn't lit up.
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
Indeed, ... I just inspected the KB2001_11.C.11 (IN) partitions and there are some new A12 partitions named my_something and old A11 reserve one is gone. Plus: almost all sizes of the common OOS A11 A12 partitions changed.
[OnePlus 8T Guides, News, & Discussion] sharkie405:
https://xdaforums.com/t/oxygenos-12-beta.4383689/post-86562887
[OnePlus 8T Guides, News, & Discussion] BillGoss:
See https://xdaforums.com/t/oxygenos-12-beta.4383689/post-86562887
[OnePlus 8T Guides, News, & Discussion] BillGoss:
The my_* partitions are only logical (they get written to super) not physical partitions.

The size of the payload files reflects the content written to the partition only - they are not full partition dumps. To see if the actual physical size has changed you need to check /proc/partitions of the running system.
[OnePlus 8T Guides, News, & Discussion] IAMAB:
Thank you guys. This worked!! I'm so happy and relieved. Was banging my head all day to resolve it.
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
@BillGoss : do or did you run OOS 12? In that case, can you share /proc/partitions? Or perhaps someone else can?
[OnePlus 8T Guides, News, & Discussion] BillGoss:
I was on OOS 12 but now I'm back on OOS 11.
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
Kudos for courage and sharing experience. Have you then perhaps noticed partition layout differences? While on topic: when one 'fastboot flash'-es any image to corresponding (logical or physical) partition, is that not somehow equivalent to a 'dd' (apart maybe from some 'decompress' from e.g. sparse to raw)? Also, how does fastboot(d) know the (new) names? I guess one may need, for any major Android upgrade, up to date fastboot(d) in any case. PE 12 has a fastbootd and Google offers latest fastboot (I guess A13 aware already). But would one today simply be able to 'fastboot flash' A12 firmware alongside an A12 Custom ROM that yesterday had (only available) A11 firmware? If partition layout is exactly same, I guess it could work. But, of course, I am too much of a n00b and coward to try. This is why I ask experts like available here :oops:.
[OnePlus 8T Guides, News, & Discussion] BillGoss:
Great questions!

I think that it is valid to say that a "fastboot flash" is equivalent to dd - for the physical partitions.

The question about names: notice that the new partitions are all logical ones, so bootloader knows nothing about them. So there's no need for a new bootloader to flash the physical ones.

Fastbootd is a different story. Have a read of this https://source.android.com/devices/bootloader/fastbootd

Fastbootd runs in user space so something , whether boot or recovery, is already booted and, therefore, you have a running system that can make sense of both the physical and logical partitions.

Can you run an A12 rom on A11 firmware and vice versa? If depends on whether the contents of the firmware partitions used by the rom are understood by the rom.

We've seen the impact on previous updates where changes in encryption mean that rom x can't decrypt data after rom x+1 has been installed.

I know that A12 makes changes to encryption so I think it's extremely unlikely that you'll find a rom that is capable of running on both A11 and A12 firmware.
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
Actually, I think it is perfectly fine for a Custom ROM to not run on two incompatible OOS firmwares (and/or partition layouts).

But take a concrete example: Custom ROM PE A12. It currently runs on OOS A11 firmware. So either (1) it keeps requiring OOS A11 firmware or one day (2) it changes to require to run on OOS A12 firmware (lets not yet talk about A13+ but similar gap (potentially even bigger) is then present). In both case there might be some inconveniences for some users.

In case (1) OOS A12 users might need to downgrade to OOS A11 before installing PE A12. In case (2) PE A12 users (like me) might need to go back via OOS A11 and upgrade to OOS A12 before reinstalling PE A12.

In wonder if such Custom ROM install/upgrade or any TWRP addon might not be made to avoid both inconveniences and transparently help change firmware on the fly. In worst case for upgrade requiring a factory reset. For example on XiaoMi MiA1 a TWRP addon allowed to repartition stock a/b layout to allow Treble GSIs to run (with Custom built vendor).
[OnePlus 8T Guides, News, & Discussion] UltimaStealth:
My 8T KB2005 is rooted with 11.0.7.10.KB05AA, how could I update to 11.0.11.11 and keep root without having to reflash? Could I download the full zip and just patch with magisk?
[OnePlus 8T Guides, News, & Discussion] shadowstep:
Added KB2005_11.C.11 (Global) to the first post.
[OnePlus 8T Guides, News, & Discussion] mike4peace:
My kb2000 device got KB2005_11.C.11 update on ota, is it a12 and should i install it because it says kb2005
[OnePlus 8T Guides, News, & Discussion] BillGoss:
Yes, go ahead.

My phone was kb2000 also. After the updated is identifies as kb2005. But it has had no impact on its use.
[OnePlus 8T Guides, News, & Discussion] xstefen:
OnePlus8T:/ $ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/block/dm-46 586M 586M 0 100% /
tmpfs 5.6G 1.8M 5.6G 1% /dev
tmpfs 5.6G 4.0K 5.6G 1% /mnt
/dev/block/dm-47 882M 882M 0 100% /system_ext
/dev/block/dm-48 13M 13M 0 100% /product
overlay-overlay 588M 588M 0 100% /product/app
overlay-overlay 588M 588M 0 100% /product/priv-app
overlay-overlay 588M 588M 0 100% /product/lib64
overlay-overlay 588M 588M 0 100% /product/lib
overlay-overlay 588M 588M 0 100% /product/overlay
/dev/block/dm-49 897M 897M 0 100% /vendor
/dev/block/dm-50 177M 177M 0 100% /odm
/dev/block/dm-51 333M 333M 0 100% /my_product
/dev/block/dm-52 12K 12K 0 100% /my_engineering
/dev/block/dm-53 4.0K 4.0K 0 100% /my_company
/dev/block/dm-54 4.0K 4.0K 0 100% /my_carrier
/dev/block/dm-55 588M 588M 0 100% /my_region
/dev/block/dm-56 671M 671M 0 100% /my_heytap
/dev/block/dm-57 721M 721M 0 100% /my_stock
/dev/block/dm-58 4.0K 4.0K 0 100% /my_preload
/dev/block/dm-59 240K 240K 0 100% /my_manifest
tmpfs 5.6G 32K 5.6G 1% /apex
/dev/block/dm-60 224G 71G 153G 32% /data
/dev/block/loop6 35M 35M 0 100% /apex/com.android.i18n@1
/dev/block/loop5 2.0M 2.0M 0 100% /apex/com.android.appsearch@300000000
/dev/block/loop7 232K 88K 140K 39% /apex/com.android.apex.cts.shim@1
/dev/block/loop8 5.8M 5.8M 0 100% /apex/com.android.wifi@319999900
/dev/block/loop10 60M 60M 0 100% /apex/com.android.art@310925030
/dev/block/loop11 40M 40M 0 100% /apex/com.android.vndk.v31@1
/dev/block/loop14 832K 804K 12K 99% /apex/com.android.tzdata@310922000
/dev/block/loop15 8.1M 8.1M 0 100% /apex/com.android.runtime@1
/dev/block/loop16 108M 108M 0 100% /apex/com.android.vndk.v30@1
/dev/block/loop17 232K 152K 76K 67% /apex/com.android.scheduling@310733000
/dev/block/dm-63 4.8M 4.7M 0 100% /apex/com.android.conscrypt@310911000
/dev/block/dm-61 5.9M 5.9M 0 100% /apex/com.android.extservices@311313000
/dev/block/dm-62 12M 12M 0 100% /apex/com.android.permission@311410000
/dev/block/dm-64 1.8M 1.7M 0 100% /apex/com.android.os.statsd@311210000
/dev/block/dm-67 8.3M 8.2M 0 100% /apex/com.android.adbd@311310000
/dev/block/dm-65 6.3M 6.2M 0 100% /apex/com.android.media@311411000
/dev/block/dm-66 4.2M 4.2M 0 100% /apex/com.android.mediaprovider@311313020
/dev/block/dm-68 18M 18M 0 100% /apex/com.android.media.swcodec@311311000
/dev/block/dm-71 712K 684K 16K 98% /apex/com.android.ipsec@311410000
/dev/block/dm-69 11M 11M 0 100% /apex/com.android.cellbroadcast@311413010
/dev/block/dm-70 7.7M 7.7M 0 100% /apex/com.android.neuralnetworks@311310000
/dev/block/dm-72 2.6M 2.6M 0 100% /apex/com.android.tethering@311411000
/dev/block/loop27 1.6M 1.6M 0 100% /apex/com.google.mainline.primary.libs@311126000
/dev/block/dm-73 692K 664K 16K 98% /apex/com.android.sdkext@310912000
/dev/block/dm-74 3.7M 3.7M 0 100% /apex/com.android.resolv@311410010
/dev/fuse 224G 71G 153G 32% /storage/emulated
[OnePlus 8T Guides, News, & Discussion] Dior DNA:
@xstefen fwiw here /proc/partitions for PE A12 (firmware OOS A11)

# cat /proc/partitions
major minor #blocks name

1 0 8192 ram0
1 1 8192 ram1
1 2 8192 ram2
1 3 8192 ram3
1 4 8192 ram4
1 5 8192 ram5
1 6 8192 ram6
1 7 8192 ram7
1 8 8192 ram8
1 9 8192 ram9
1 10 8192 ram10
1 11 8192 ram11
1 12 8192 ram12
1 13 8192 ram13
1 14 8192 ram14
1 15 8192 ram15
254 0 2150400 zram0
8 0 247013376 sda
8 1 8 sda1
8 2 32768 sda2
8 3 1024 sda3
8 4 512 sda4
8 5 512 sda5
8 6 1024 sda6
8 7 10240 sda7
8 8 10240 sda8
8 9 307200 sda9
8 10 65536 sda10
8 11 524288 sda11
8 12 512 sda12
8 13 32768 sda13
8 14 480 sda14
8 15 7340032 sda15
259 0 102400 sda16
259 1 102400 sda17
259 2 64 sda18
259 3 64 sda19
259 4 16384 sda20
259 5 131072 sda21
259 6 131072 sda22
259 7 131072 sda23
259 8 1048576 sda24
259 9 1048576 sda25
259 10 307200 sda26
259 11 307200 sda27
259 12 235360108 sda28
8 16 8192 sdb
8 17 5120 sdb1
8 18 128 sdb2
8 80 131072 sdf
8 81 104 sdf1
8 82 2048 sdf2
8 83 2048 sdf3
8 84 2048 sdf4
8 85 128 sdf5
8 86 2048 sdf6
8 87 2048 sdf7
8 88 2048 sdf8
8 89 4 sdf9
8 64 2621440 sde
8 65 512 sde1
8 66 4096 sde2
8 67 8192 sde3
8 68 524288 sde4
8 69 1024 sde5
8 70 4096 sde6
8 71 32768 sde7
8 72 8192 sde8
8 73 65536 sde9
8 74 512 sde10
8 75 98304 sde11
8 76 512 sde12
8 77 512 sde13
8 78 128 sde14
8 79 80 sde15
259 13 64 sde16
259 14 24576 sde17
259 15 2048 sde18
259 16 32 sde19
259 17 32 sde20
259 18 32768 sde21
259 19 128 sde22
259 20 2048 sde23
259 21 16384 sde24
259 22 512 sde25
259 23 4096 sde26
259 24 8192 sde27
259 25 524288 sde28
259 26 1024 sde29
259 27 4096 sde30
259 28 32768 sde31
259 29 8192 sde32
259 30 65536 sde33
259 31 512 sde34
259 32 98304 sde35
259 33 512 sde36
259 34 512 sde37
259 35 128 sde38
259 36 80 sde39
259 37 64 sde40
259 38 24576 sde41
259 39 2048 sde42
259 40 32 sde43
259 41 32 sde44
259 42 32768 sde45
259 43 128 sde46
259 44 2048 sde47
259 45 16384 sde48
259 46 4 sde49
259 47 1024 sde50
259 48 256 sde51
259 49 256 sde52
259 50 32768 sde53
259 51 4 sde54
259 52 4 sde55
259 53 8192 sde56
259 54 65536 sde57
259 55 128 sde58
259 56 512 sde59
259 57 28 sde60
259 58 128 sde61
259 59 4096 sde62
259 60 2048 sde63
259 61 65536 sde64
259 62 32768 sde65
259 63 307200 sde66
259 64 16192 sde67
259 65 32384 sde68
259 66 16192 sde69
259 67 16192 sde70
259 68 16192 sde71
259 69 8096 sde72
259 70 16192 sde73
259 71 16192 sde74
259 72 16192 sde75
259 73 128 sde76
8 48 131072 sdd
8 49 104 sdd1
8 50 128 sdd2
8 51 2048 sdd3
8 52 1024 sdd4
8 32 8192 sdc
8 33 5120 sdc1
8 34 128 sdc2
252 0 1412 dm-0
252 1 1691904 dm-1
252 2 972144 dm-2
252 3 446904 dm-3
252 4 1050504 dm-4
252 5 235360108 dm-5
[OnePlus 8T Guides, News, & Discussion] azoller1:
Have the my* partitions been around oos for awhile? Literally what are in those partitions lol I'm sure the my_company partition is soo critical.. Wonder if other devices have these partitions..
[OnePlus 8T Guides, News, & Discussion] Some_Random_Username:
my_ * partitions have been introduced with OxygenOS 12, likely as a consequence of codebase merge with ColorOS.
[OnePlus 8T Guides, News, & Discussion] BillGoss:
They are (new to OOS) logical partition - just like system, vendor, etc - so only present in the super physical partition.
[OnePlus 8T Guides, News, & Discussion] tahasmarty:
After Upgrading OXYGEN OS 12 Can't disable google bloatware apps :( any solution for that? I don't want to ROOT my phone please..
[OnePlus 8T Guides, News, & Discussion] antil00ppi:
I noticed same, I'll try this XDA guide probably soon. (2005 11c11)

How to uninstall carrier/OEM bloatware without root access

If you want to get rid of carrier/OEM apps from your phone, here's how you can uninstall bloatware from your device without root access!

www.xda-developers.com

Does others have size issues regarding resolution, font size and size of other elements? I mean everything is too big (too low resolution) in my phone now using oos12 kb2005 11c11)

It seems that changing smallest width does not have effect to oos12 launcher or apps.

Have someone tried to change value at system/build.prop in line ro.sf.lcd_density (does it even exist in android 12? ..needs root..)?
[OnePlus 8T Guides, News, & Discussion] tahasmarty:
Thanks wil try the guide and if you have font issues try this setting.
[OnePlus 8T Guides, News, & Discussion] antil00ppi:
Yep it was first setting I tried, can make things only larger in my case.

fyi I debloated oos12 successfully

For those having same problem that I have don't waste time with factory reset, it won't fix size/resolution issues, tried already :D.

Problem could be also somehow related the fact I was EU and now automatic updates pushed me global.

I'm still not going to rollback (again) anytime soon, too much work downloading things and setting things up, I'll wait fix for this or if los19 will be released, I'll flash it.
[OnePlus 8T Guides, News, & Discussion] acme anvil:
Have you tried modifying it in Developer options?
[OnePlus 8T Guides, News, & Discussion] antil00ppi:
It did not survive reboots (goes back randomly either to 423 or 320) and well did not make launcher artifacts smaller (some items took effect). Also apps either did same or were not affected at all.

I recommend oos team to make smaller options directly to the settings and separate applying font size from applying screen size.

I had same issues on open beta.
[OnePlus 8T Guides, News, & Discussion] TanakaX5:
Yo,

Just out of curiosity, is your device a KB2003? And did you flash the international c11 on it?

I'm trying some things to fix the resolution problem for the eu Variant.

Greets,

T
[OnePlus 8T Guides, News, & Discussion] antil00ppi:
I had latest 2003 version and flashed 2005 in it via phones local updating function to open beta 1, it sucked because of this resolution thing so I did rollback and lived happily with OOS11 again till c11 stable were pushed via OTA.

I really do not have more detailed info.

edit. I really appreciate efforts to try fix this problem if someone else has or had it
[OnePlus 8T Guides, News, & Discussion] planttt:
My Oneplus 8T Cyberpunk kb2000 device got KB2005_11.C.11 update on ota, is it a12 and should i install it because it says kb2005
[OnePlus 8T Guides, News, & Discussion] BillGoss:
I'm running KB2005_11.C.11 on my KB2000 8T without problems.
[OnePlus 8T Guides, News, & Discussion] Pyntux:
Can I install that KB2005_11.C.11 with offline install over Android 11 BA (Europa version rom)? Phone is KB2000...
[OnePlus 8T Guides, News, & Discussion] BillGoss:
That should be ok.
[OnePlus 8T Guides, News, & Discussion] Devar Bl3nd:
Can i downgrade O11 BA with O12 11.C.11 AA ? My device is KB2005
[OnePlus 8T Guides, News, & Discussion] BillGoss:
Because of the changes in encryption, you can't do a simple install of OOS 11 BA from OOS 12.

I would suggest you use the downgrade package provided in the official OOS 12 announcement (https://forums.oneplus.com/threads/oxygenos-12-for-the-oneplus-8t.1555060/). It will install OOS 11 AA and format userdata (reset your phone). Then you can manually install the BA version you want.
[OnePlus 8T Guides, News, & Discussion] Devar Bl3nd:
how to install BA version then i downgrade to O11 AA? (First time i use 1+)
[OnePlus 8T Guides, News, & Discussion] BillGoss:
How did you go from OOS 11 BA to OOS 12?
[OnePlus 8T Guides, News, & Discussion] Devar Bl3nd:
no, Now i want OOS 11 AA to OOS 11 BA
[OnePlus 8T Guides, News, & Discussion] BillGoss:
Tell me what you were on before you had OOS 12 and how you installed OOS 12.
[OnePlus 8T Guides, News, & Discussion] Devar Bl3nd:
i update OTA to OOS12 from OOS11, now i downgraded to OOS11 AA
[OnePlus 8T Guides, News, & Discussion] BillGoss:
Download OOS 11 BA from the first post on this thread, move the downloaded zip to/sdcard (not in a lower directory) go to Settings>System>System update>Gear icon and tap on the file you downloaded.

That's called a manual install.
[OnePlus 8T Guides, News, & Discussion] Devar Bl3nd:
can you tell the difference between BA and AA?
[OnePlus 8T Guides, News, & Discussion] BillGoss:
One says AA and one says BA?

I couldn't tell that they were different.
[OnePlus 8T Guides, News, & Discussion] VarunAgw:
Deleted
[OnePlus 8T Guides, News, & Discussion] azoller1:
Just got notification for new update for KB2003.
[OnePlus 8T Guides, News, & Discussion] jcsww:
I wonder if that update kills the dual-SIM function on the KB2007 like the Global/NA Android 12 update did.
[OnePlus 8T Guides, News, & Discussion] azoller1:
Well I hope it won't for me. I need dual sim 😨
[OnePlus 8T Guides, News, & Discussion] jcsww:
Let me know how it goes for.you. I need dual-SIM as well and it has to be on a T-Mobile sold device because I go into areas where I need domestic roaming on to the US Cellular network.
[OnePlus 8T Guides, News, & Discussion] Pyntux:
I got same update (BA - Europe) on my KB2000... I will update later and report if anything is wrong with that update....

Edit:

Everything is OK for now... dual sim works, but now my phone is not KB200 in settings anymore, now is KB2003...