Nope, I think we're on the same schedule as last year. Here's a post from last years thread:
http://www.greekchat.com/gcforums/sh...2&postcount=27
Notice the date on the post--I think that puts bid day the first Monday after Labor Day.
The reason U of I has moved bid day to a Mondays is not for Labor Day but Rosh Hashanah.
Eta: I do believe I was around for bid day over Labor Day weekend, but I think this is the 3rd year they have moved to this schedule