Moving between Play store subscriptions

Hey I have an app that we are charging monthly subscriptions for users.

In the App Store we have created multiple subscription groups so that we can charge for different levels of service that the users can move between as they wish.

Q1. I would have preferred to have multiple subscriptions within one subscription group but apparently this is not possible within BDK. Can anyone confirm?

Q2. In the Play store I am having an issue allowing users to move between subscriptions at all. Is this possible within BDK, obviously it’s possible in native apps?

All and any help much appreciated.