The source page for EU Android 12 firmware says it can be flashed to US and IN devices too, coming from Android 11 firmware. Would be weird if it didn't work on TMobile, especially because I was able to convert it to Global on Android 10 and upgrade all the way to stock OOS 12 with no issues (an upgrade that necessarily installs A12 firmware)SORRY NO OOS 11
I have the same phone OOS 11 Firmware.
Latest tmoble Firmware
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Edit: The directions for the A12 firmware based builds in the telegram chat tell you to update to the latest OOS and flash EU Android 12 firmware (which should work on IN/US devices also) before flashing the Android 12 build. It specifically says not to flash OOS12, so the lack of a t-mobile OOS shouldn't matter (doubly so because I converted it to Global) That is where I encounter issues. For the builds in this thread obviously you need to be on A11 firmware.