There was some info in a dev Q&A here…
Namely, this bit:
Forums question – Do we get an ATC [air traffic control] overhaul together with the redesign of the AI [artificial intelligence] traffic system? - Timestamp
Marital: Overall, we are still trying to add layers of improvements. So now, we are working on improving the vectoring not for Sim Update 10 but just after. Just to improve the ATC vectoring. And also, we want to make use of the MSAs for minimum safe altitude. So that should include on the flight planning formation, and it would change the way the ATC is using the flight plans, also. So layers of improvement. No reboots, I would say.
So it sounds like it will get worked on and an update due just after SU10, so likely the Q4 2022 release (maybe, this was said back in May). I think it’s a difficult enough system problem that they should probably just open up the API for traffic/weather a bit more and then let 3rd parties wail on it in more depth.
Also, the latest feedback snapshot here