Wow! Thanks for all of the responses!
I feel like this SHOULDN'T be a big deal, but I'm finding that there are lots of things that I can't imagine someone caring about that they really, really do.
I switched packs this year, from one that interprets "end of school year" literally (June 20ish, here!) to one that uses May 31 as the end, and has traditionally done the bridging at the May pack meeting. So, I was thinking these boys would have 3 months to try to finish everything, if that was something they cared about, and found out just this week that we have just over 2 months between now and the crossover. Eep. That means taking a pair of scissors to some of the elective stuff I thought the den was going to get done, too!
The information about flexibility in deadline is helpful. My main concern is the Howling at the Moon campfire requirements and camping. We're trying to get another camping trip lined up for this year, but it would be either late May or June, so after our bridging. My guess would be that if they don't get the rank patch at the same time the other boys earn it, they won't care two weeks later and just won't earn it, but extending the deadline helps put a "haven't finished it YET" spin on it in the moment instead of feeling like they failed. And helps me feel like we did our part trying to offer a reasonable path to reach that goal if it's something they care about.
So, something like the face painting for each rank - that would be tied to the den the child is entering, not the rank earned?
I'm not sure whether this is exactly the script followed in our pack, but something along these lines http://www.scoutorama.com/ceremony/ceremony_display.cfm?cer_id=24
Thanks!