If they meet tomorrow and decide to add (and who to add) tomorrow - then I'd be telling the invitees that they've got till Monday Morning at 8am at the latest to give their answer, because there's going to be a press conference announcing the new conference members at 10am.

If they want to add 4 teams, invite 4 teams, and only 3 teams have responded by 8am - I'd still do the press conference announcing the three additions. And if they want to say there is more to come and/or they are continuing to explore the potential addition of new members - great.

It just feels like they'll want to gain some stability sooner rather than later - including extending the grant of rights of existing and new members for a few years longer into the future and/or some pretty steep exit fees.