The B1G has said they will not add woman's hockey because the WCHA is so strong compared to everyone else.
I don't see Notre Dame joining the B1G in hockey, I'm sure the ACC will find a way to stop Notre Dame from joining the B1G in any capacity.
I've been told that Yost won't expand or be replaced because it's the right size for the amount of people attend games there. Yost still has a good atmosphere for its size and looks like attendance has been stable there compaired to Minnesota and Wisconsin.