I use yearly subscriptions with a 7 day free trial period in my app.
Google released the v3 of its billing library and sent emails to developers + wrote blog articles in order to ask an upgrade to the v3 by November 2020.
Namely, any app should manage the 'Account Hold' status by November 2020.
Implementation of the 'Account Hold' stuff requires the use of RTDN / Pub/Sub:
https://developer.android.com/google/play/billing/subs#account-hold
Problem: I really don't understand how to implement all this mess.
How do I implement 'account hold' for yearly subscriptions with a 7 day free trial period in my Android app?