A: Yes, using fastboot flashing lock . However, this will wipe data again. Only relock if you are 100% back to stock Realme UI Android 11, or you risk a hard brick.
A: No. Downgrading via rollback packages triggers anti-rollback. You would need to unlock first on Android 11 before flashing any Android 12 ROM. realme x2 pro bootloader unlock android 11
A: Realme resets quotas at 10:00 AM Beijing time (GMT+8). Try exactly at that hour on a weekday. Avoid weekends. A: Yes, using fastboot flashing lock