So I changed my Master Password on 1Password 4 for Mac (dropbox sync).
The iOS version took the new password (as expected) but I was forced to enter the old password to be allowed into the android app after several rejected attempts trying my new password.
After the automatic dropbox sync I locked the app and relaunched it. I was greeted with the "quick PIN" screen. Shouldn't the master password appear when we specifically select lock from within the app?
Anyway I terminated the app and relaunched it and at this point I could insert my new master password which it accepted.