[Samsung Galaxy Tab S7 / S7 Plus Guides, News, & Di] AnonVendetta:
I haven't been on xda in awhile (over a month). Been busy settling into my new apt/job, so not much time for messing around with Android's innards. In my last posts, I forgot to link to the steps I personally use.

TWRP for the Samsung Galaxy Tab S7+ 5G (T976B)

I'm stuck in TWRP loop with the new T970XXU1ATK3 firmware won't boot to system after the update. Is there anyway to fix this issue?

xdaforums.com

I've been using those steps for many months, they work on 11, 12, and 13. It's pretty much the same steps for all. I believe in not deviating too much from a method that has consistently worked, and still works.

It's best to use latest Odin, which is 3.14.1. You don't need the patched Odin.

I used to own the wifi only SM-T970, but now have a SM-T976N. They are both Tab S7+, the main difference is that one is wifi only, whereas the one I have now has wifi, 4g, and 5g connectivity. They also vary in terms of storage space/available RAM. The SM-T976N is the best Tab S7+ model, because it has the most space, RAM, and available internet connectivity options. It defaults to Korean language, but English is selectable while setting it up. Overall, the core hardware set is 95% the same for all Tab S7+ models.

For the t970, there is no carrier specific US firmware, since it can't have mobile data connectivity. US firmware for this model goes by the codename XAR. You can also use European EUX, there's no substantial difference. All Tab S7+ models are multiple language enabled, so it doesn't matter much which firmware you choose.

If you're using Windows, Frija is the best way to get the latest firmware. Use SM-T970 for the model, and XAR or EUX for the csc/product code. Unpack the zip, flash with Odin. For a clean flash, use the csc tar file. For an upgrade flash, which doesn't wipe data partition, use the home csc tar. I suggest a clean flash. And you must choose one or the other csc tars, you can't use both.

You can unlock or relock bootloader at any time, but it will wipe out the data partition/internal storage. And don't relock if you're running a custom anything, you must be on 100% official firmware, or else a softbrick will ensue.

You can flash updated firmware after rooting, but it can get hairy and you might lose root/twrp/other mods. It's so much simpler to flash latest firmware before unlocking/rooting, you will save a lot of time.

I do highly recommend using the latest available Android 13 firmware, no need to be afraid of updating. Just update first, then root and unlock later. The Tab S7+ is nearing the end of its' lifespan in terms of official updates, Samsung has already stated that it won't get Android 14. I suspect they will continue putting out updated firmwares awhile longer, but it will only be security updates. No major stuff like new software features or the latest OneUI.

If you want to go a step further, you can run a custom gsi ROM like AOSP or LineageOS in place of stock. Awhile back, I posted a method that will let you run a gsi as primary ROM, while having stock ROM as a secondary. I believe my method is new and previously undiscovered by no other Tab S7+/Note 20 Ultra users. I made this discover by testing and pure chance. I'd always known that I could run non-stock gsis as a secondary rom, but I became curious and decided to test stock as secondary instead. If interested, Google for "Tab s7 gsi" and check my more recent posts in that thread.