Hi everyone!

Recently I tried to flash my umidigi A9 pro with dotOS(GSI). At the time I didn’t know that dotOS is based one android 11(the same version that my OEM ROM was). Now I want to install leafOS(still GSI). I read online and some page said I need to reinstall OEM rom before install new one. Other said I just need to wipe everything then just install via fastboot(adb). Right now I am a bit confused on this subject, so any help would be appreciated a lot. Thanks in advance!