well, they can rehearse off of the stage as long as they are able, which is where all shows start rehearsals. They just won't be able to move to the stage until the strike is over.
so, I guess once the beginning rehearsal period is over, they will have to break, and then start up again on stage, refreshing themselves as they go along.
"I'm an American, Damnit!!! And if it's three things I don't believe in, it's quitting and math."