Deadline for absentee bidding

You can leave absentee bids during the auction 10+ lots ahead of the item currently up for auction.

You can retract absentee bids up to 2 hours before the auction begins, after which point your bid amount is unable to be removed.

The only way to remove any unexecuted bids from the auction after the 2 hour window has passed, would be to contact the auction house directly and request that your registration be declined.