Hi!
I have several rk3318 boxes at hands (H96 Max, X88 Pro) - all of them android 10.
I've tried to burn Buster legacy and Focal mainline to sdcard, but no success - it still boots into android.
But when I burn Multitool image to same sdcard, all boxes boots fine to multitool.
Maybe I'm doing something wrong? I used balenaetcher to burn sdcard.
The boxes are not mine, so I cannot dissassembe them or reflash emmc.