So the way I understand it, there was what looked like a ragequit last December:
https://github.com/markqvist/Reticulum/blob/master/MIRROR.md
(sorry for the github.com link!)
... but after a few weeks of a break code began being pushed again to github.com but solely as a mirror.
More explanation was published a few weeks ago here:
https://github.com/markqvist/Reticulum/blob/master/This Is Not a Teahouse.md
(again as mirror)
The way I see it: Mark Qvist stepped back from github and through this gesture formulated quite an acid criticism of what free/libre software became as commodified by microsoft/github: standardisation of the roles (multiple!) of maintainer revolving around the following: expectation to be publishing code AND to be a public front for the software / obligation to do tech support and answer any request even the most stupid ones / judgement on how well you will manage everyon's sensibility and ego in the process / etc.
It's well explained in the seminal "this is not a tea house" text. Mark Q. likes to produces code and that what he is apparently good at. He will now focus on doing this and just this, and others can decide what to do with it (and it seems to be working well to be fair).
To put his code where his mind is, he also transition the main source for the reticulum code to rngit as of one of the latest releases (1.3.4).
I am personally impressed and confident that his criticism of the "auto-entrepreneur/tech-supporter/influencer maintainer" (my words) will ripple and inspire others to realize the toxic influence and monoculture github culture has instilled in free/libre software.
A lesson of (software) freedom overall!
Go, Mark go! and go Reticulum! 