@N8LBV said in Update 2.7.0 Dev to Stable process?:
I did not see this in the upgrading docs.
I'm not surprised it's not mentioned there. As I mentioned, the typical pathway would be DEVEL --> RC --> RELEASE, and that pathway is supported. Upgrading from RC to RELEASE is supported because when the RC is available, development there ceases. The only exception would be if a huge showstopper problem was found. In that case RC might get an update, or might even be pulled and the branch fall back into DEVEL.
The problem is that the versions of critical pieces of the OS and supporting shared libraries change as the next DEVEL version progresses. Each DEVEL update can move the DEVEL and RELEASE branches farther apart at the kernel and shared library levels. There rapidly approaches a point where you can't go backwards.
I don't know what your level of expertise is with FreeBSD software development and software development in general, but OS and shared library versions are very critical to other software running on a platform. pfSense is FreeBSD at its heart, but it is a slightly modified FreeBSD kernel. The GUI you see is handled by PHP. Changes to only PHP source code would normally be fairly easy to "downgrade". But if something in the kernel or shared libraries changes, that is not easy to "downgrade". By "downgrade" I'm talking about moving backwards from a DEVEL version to RELEASE.
A really big change between 2.6 and 2.7 (and now 2.8 DEVEL) was the move to PHP 8.x from PHP 7.4.