Thanks for the fast and detailed explanation! Beta aka test-passed branch is less suitable for me). I just wonder to know if stable branches still develop after release 
I’ve been supporting two Discourse instances since October 2017 after migrating from different forum engine. We use Discourse as a platform for customers and we are software developers familiar with beta-state, therefore it is better to have predictable forum than beta version. Too many surprises may happen during beta-period 