[AT&T Samsung Galaxy S7 Edge Guides, News, & Discus] Xak:
I have managed to downgrade from firmware PK1 and even get Echoe rom multi carrier working on it and flashed G935U.

First root phone

Then Flash G935U

Skip set up except google account set up

download chrome

= Before re rooting download echoe rom to sd card else downloads will be slow <-- keep it on sd card until you successfully flash it

=Download Echoe rom from Verizon S7 edge Thread version 1.5 by original developer it is still multi carrier

= Also id download Xposed framework material apk and framework itself and move to sd card or xposed of your choice other than framework which is always 64 bit

Once echoe rom is downloaded go to my files. select echoe rom with long press and move to external sd card

Now root the G935U after youve downloaded flash fire and rom frameworks moved them to sd card.

I set Super Su to automatically grant root permission so its faster.

Now open flash fire

Click + add wipe , select everything on the wipe menu option and everything literally. <-- Repeat this 3x

Click + add wipe , select everything on the wipe menu option and everything literally.

Click + add wipe , select everything on the wipe menu option and everything literally.

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Make sure the 3 wipes as mentioned above take place before you do add flash zip rom, you might have to drag them to the top

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Click + fash zip ota select external sd card from dropdown and select ehcoe rom on sd card <-- might also click mount read/write and auto mount

Click +, wipe only select Dalvik cache , and Cache partition (do not select format cache partition) <--- 3x repeat

Click +, wipe only select Dalvik cache , and Cache partition (do not select format cache partition) <--- 3x repeat

Click +, wipe only select Dalvik cache , and Cache partition (do not select format cache partition) <--- 3x repeat

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Make sure these are below the flash of the rom which is below the three wipes from above.

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Flash fire will take a while now. Then you will echoe rom aroma installation if youve done this correctly.

Note: on aroma installation only select S7 camera app not note 7 camera app and do not select to remove any TTS from google or samsung or some functions may glitch and youll have to repeat all of this. also select AT&T for the carrier assuming your on att if your on att thread even though its verizon multi carrier rom.

After echoe rom aroma installation is finished be patient and wait it will go back to flash fire do not freak out if you see a black screen it will then wipe cache and dalvik 3x like most people do when they have TWRP recovery

Also if you find your self in a bricked situation go to download mode and use Prince cosmey odins only or it will not work. and download only G935A Pi2 firmware from a thread created by mod77 or someone like that that is the only firmware that will take you back to stock, also regular updates will work once or flash pi2 so we will be on normal ota no matter what even after rooting and going back to stock

sorry for this bad written post i havent posted on here in a long time hope i helped some

also for odin you will need to change com port to port 4. click Windows key+x than device manager -> then select dropw down arrow of communication port or Ports (COM & LPT) right click the menu item below that and hit properties -> then port settings tab -> than advanced button, then com port number dropdown on bottom left and select port 4. Also make sure you are using original samsung s7 edge or other white samsung device cable no other brands cables will work and samsung usb drivers. then click ok.

i again do not take responsibility for anything that happens to your phone or device