When is Deadline to Team up?

I have two questions about teaming up:

  1. When is the deadline to team up? (In the “timeline” section of website it says May 28th, and in the “participation and submission” section it says May 21st).
  2. Can participants team up if their combined phase 2 submissions exceed 6? (The submission limit for phase 2 is “each team can make 6 total submissions across all three tracks”. If participant A has 6 phase 2 subs and participant B has 6 phase 2 subs, can they still team up? because after teaming up their team will have 12 phase 2 subs).