I am currently looking into how to deal with price change.
The documentation suggests communicating with the user when application starts. To start the price change confirmation flow, the documentation indicates the application can determine if the user has a pending price change by looking at the priceChange field in the subscription resource. (available through a REST API) If present, this field indicates the subscription has a price change, and the priceChange.state field indicates whether the price change has been accepted or is still outstanding.
Is there any corresponding Google Play Billing Library API that would provide the same information?