I have posted the solution in post #4 Have you tried it? It is the procedure for updating existing app to aab, no need for PEPK
If you are UPLOADING A NEW APP, then you need to create a new Keystore File, which you can do with B4A v10.9 beta
or you follow the steps here
There is an increasing concern about how to publish apps using the app bundle (aab) format. I will try as much as possible to simplify the steps for you. IMPORTANT UPDATE IN POST #3 OPTION 1: Creating and Using New Keystore File This option can be used by those who are new and about to create...