Looking around online, further rumors seem to lean towards it being a Federation origin film.

That would put us in ENT era, but I don’t see them following the existing canon. Maybe following a non-Enterprise ship to recruit an early but non-founding planet. The origin in this case being about how the Federation first expanded.

The other option could be picking up right after First Contact. How mankind adapts to learning about the Vulcans.

I just don’t see either of those films getting greenlit.