Fork of the isabelle-dev vs. isabelle-release in approx. 24h

[Makarius]

The all-important fork of the isabelle-dev vs. isabelle-release will happen 
03-Oct-2026 12:00 Royal Bavarian Time.

Afterwards anything pushed on the isabelle-dev repository will be for the next 
release, after Isabelle2026 (October 2026). Anything for the current release 
needs to be send to be via E-Mail (e.g. result from "hg export").

We still have a few odd technical problems to sort out, e.g. the question if 
z3 really works on arm64-darwin and arm64-linux.


In the meantime NEWS and CONTRIBUTORS might need additional attention.


	Makarius