Recently, I upgraded a Redmi 7A to Andy Yan's Personal Build #GSI #LineageOS 20 and the base vendor OS to V12.5.3.0.QCMEUXM. The difficulty there was that I had to reflash the userdata.img from V10.2.5EU else the LineageOS 20 got stuck in the boot animation while the USB Debugging adb logcat showed it was failing to find data/misc/certstore repeatedly. I hope this note helps someone in the future (maybe even me!)