SQL Reporting :: Combine Column Group Columns Into One?

I have a dataset like this:

BidID....DistributionMonth....LbsRemaining

1...........08-2010.................50,000

1........... 09-2010................25,000

1............10-2010................25,000

1............11-2010................100,000

I have a report that shows this data by pivoting on the month and giving the remaining amount, like this:

BID......Aug-2010 Remaining........Sep-2010 Remaining.......Oct-2010 Remaining........Nov-2010 Remaining

1..........50,000...............................25,000...........................25,000..............................100,000

This all works just fine. However now, I want to take a date that's given, and make a "Past Due" column for anything less than the first of the month of that date.