I want a way to set Briar so that the app connects at an interval of X for Y minutes to synchronize messages.

As a second possibility, a period where Briar connects to synchronize messages. For example between X and Y o'clock every day.

The idea behind it is to make online time more effective due to the high battery consumption. Two users could agree to configure their Briar Apps between X and Y to go online and synchronize messages.