Currently 4.11.x isn't even 'stable' – it is a 'maintenance mode' release (which means it is just being kept for the people who need it, for some reason.)

It makes sense for us to start work on moving – at least – to samba 4.12.x (latest stable) before 4.11.x goes away.

I don't really require 4.12, but it becomes harder to maintain a very old version of samba that will be unsupported upstream.