After @geiti94 and @ianmacd started the ball rolling for the Samsung Galaxy S10 series (Exynos 9820), it was really only a matter of time until we could do the same for the 2019 Galaxy Tab A 10.1 (Exynos 7904). The kernel source was released last May, allowing me to build a custom kernel with many of the problematic Knox security features disabled. What's posted below is a work in progress, but it should suffice to unblock efforts to build custom ROMs for this impressive tablet.
The current process requires you to reset to factory defaults to remove file-based encryption. Remember to backup your data!
Custom kernels are specific to OEM releases, and rely on the latest posted kernel source (T510XXU4BUA1).
This is unofficial and unsupported, so the usual caveats apply. Since we don't flash the bootloader, you should be able recover from any problems...but nothing is guaranteed.
From existing TWRP install: (No need for data wipe.)
Hold Power & Vol Up during restart to enter TWRP recovery
Tap Install->Install Image, select your image (.img) file, pick Recovery partition, and then swipe to install
Reboot to system
What about rooting with Magisk?