I have an apk with version code 64 on Alpha group, then I want to promote it to Beta phase. What happens to the users on the Alpha group that haven't downloaded that version yet? Do they will still be able to update automatically to that version (that will be on Beta for now on)? Or will they get stuck into past version, since into Alpha test I will have no published apk anymore?
Please refer to https://support.google.com/googleplay/android-developer/answer/3131213?hl=en
The two interesting points for your case: