Debian currently stays with Tinc 1.0, while Tinc 1.1 is present in
"experimental".

Backward compatibility between 1.0 and 1.1 is absent, users will have to redo
their network configs on upgrade - and must do that all at once on all their
network nodes. It is a huge and in some cases unsurmountable burden. It might
as well be a different piece of VPN software entirely, might as well migrate
to WireGuard.

To tackle this I suggest providing 1.1 as a separate "tinc1.1" package, which
would let users have *both* installed and allow for gradual migration of large
networks, even setting up routing or bridging between old and new as necessary.

Another alternative is to stay on the version 1.0 "forever" which seems to be
the course chosen already. Nothing wrong with that either. But if you look into
an upgrade path, I described one way it could reasonably proceed.