Restring a uke before or after a crack repair?

I got a great deal on a Ohana TK-38 because it has two cracks on the top behind the bridge. I'm taking it in tomorrow to get the cracks fixed but I also have new strings for her and I'm going to be bored tonight. Would it make a difference if I restrung her tonight or should I wait until after the repair is done?

I'd wait.
Most likely, they'll have to take the strings off to work on it.
There's no advantage to putting new strings on now, and there's a possibility that the strings could get nick'd when they work on it. Also... some people say that detensioning strings makes them sound worse. I'm not sure I believe it yet, but all things considered, there's no advantage to putting them on now.

Better to wait until the top is repaired and stable before restringing.

I'd certainly wait! In fact if one of my ukes cracked, first thing I would do is loosen the strings until I had it repaired. Remove all stress from the uke!

Yes I always like to install a new set of strings after I get it fixed and cleaned up, it also helps the luthier get the intonation set right with a new set