....don't give up!
Doing the happy dance now - I finally got the last night I need in Housekeeping Camp, for the first week of June. Back when I first started making *very* last-minute reservations, in April, there was nothing at all in HKC for my week, so I booked Curry Village. Between checking the website and calling in every day, I started cobbling together single nights in HKC and now I have in my hot little email folder, a confirmation for 5 nights, in a river unit no less!
Anyway, I post this to encourage anyone else out there - don't give up when you see lack of availability. Make a back-up reservation (that you could a) cancel and b) still enjoy if you're stuck with it) and keep checking!
Now off to cancel Curry...
Did I mention I'm happy? :-)