well the games are on the 29th/30th, if schroder's team doesn't win their playoffs (and even if they do, if they don't get the invite to the frozen 4)
then he COULD join as early as the 15th (if they get eliminated this weekend and he chooses to leave school immediately after the season). if they make it to the second round but not the frozen four then he could join on the 21st (again, if he chooses to leave school to go pro).
As for Hodgson, his team finishes their regular season on the 14th, and they start the post season around the 16th. if they go 7 games it could be around the 28th before he joins the team (or even later if they make it to the second round and beyond) if they get ousted in the first round (especially early) then he would be there. if it goes to 7 games, he may be there for the second game, but I would doubt the first game.