It's rather wishy washy - I tried to take my kid to the library yesterday while in the 4-day bucket with two ahead of me. They called me in for Ready Reserve as well as the two ahead of me. I've gotten 'caught' out in town four or five times now but have always made it (I live close to Athens, a 1hr15min commute).

Not sure how the holidays will work but if you bid reserve for Jan/Feb and don't select call me first, you'll rarely get called and it will be much more predictable.