Did you tried the Lineage OS 17.1 for Samsung Galaxy Note 10.1 2014 based on Android 10 Q? I upgraded my note 12.4 pro. Everything works fine except the bluetooth hangs from time to time.
i tried flashing back Lineage OS 9 from backup but it would not boot up and is soft-bricked i can only boot into download mode and only twrp-3.1.1-2-dreamlte.img works, all other's fail to boot (just freezes on TWRP logo and sometimes flickers black as it re-trying)First turn off the tablet. 2. Next press and hold "Power" until you see the manufacturers logo on the screen, then release the power button. 3. "Quickly" press "Volume Down" and hold it for few seconds until you see the message "Safe mode: ON" or something similar. 4. 5pfOV.