Pretty sure they'll be just fine.
I know it is not exactly the same but I use to make sourdough bread. Captured some wild yeast from the environment, built a starter that was used as needed, fed and kept in the fridge for years. Even at fridge temps the starter would grow and often times I made my bread dough at night, put it into the fridge, it would "grow" some, pull it out the next day and let warm back up to room temp. I'd then make the the loaf and let rise till ready for the oven... hours usually
The cold temps didn't hurt the yeast at all, actually it brought out character
If brewers yeast is half as resilient as bakers yeast.. a few hours in water will not harm it.