There really aren't that many skilled, mentally healthy people who actually want to work overnight/holiday shifts. It's pretty much always the guy who drew the shortest straw or desperately needs the night shift differential
I can't imagine it'd be that hard for a corporation the size and global breadth of Apple to find workers in their European, Australian, etc. offices to do "overnight" shifts during their daytimes, and I've known Jewish/Muslim/atheist/Hindu/etc. folks who love holiday pay.
I had the opportunity to talk to two ladies from the review team in person at a recent Apple event and my impression was that they really know what they're doing.
Weird given the completely ridiculous decisions that come out of that team. I wonder if they're tremendously overworked or if the skill level of their staff is wildly inconsistent.