Well , I do wonder if Gaozu will still have an active roster to play for this season in Dota 2 pro because there are plenty of carries available as long as the project is valid. Personally , I do hope that Yatoro will choose to return around this year with a strong team and personally I think he will go to Team Liquid as I don't see Micke resisting under this massive pressure for long but this is just my theory.
For now, it's unlikely for the veterans to return, I heard Xinq and Dy were set on taking a step back from the scene and I also think it's not worth the effort to create another squad when everyone is fighting for that one spot in the qualifiers.
Maybe next year, once the next qualifiers of DreamLeague start there could be a possibility for them to run it back or even merge with Team Turtle (Fy's stack).
I have no idea when Yatoro will return, but he still has a contract with Team Spirit so I assume he'll stick with the squad just like Collapse's return and Satanic will return to the second team.
Anyway, who has an idea on who are invited teams? the LQP page still says nothing except the qualified ones.
We might have to wait a little longer as they haven't made any announcement regarding the invites.