Chris Yates, a member here, mentions on his blog that when he started a listing at Flippa and abandoned it, Flippa's (automated?) systems got back to offer him a 40% discount to continue with the listing.
He speculates that it may be only because his site was a quality site with high traffic/revenue but, of course, not knowing the site in question it would be worth trying this on any listing at Flippa. Bear in mind that Flippa have no way of properly verifying traffic and revenue claims for all sites so it's entirely possible the 40% offer is made to any half done listing that's not taken to completion. Given that from the end of May to now the number of Open Listings on Flippa has dropped by 25%, it's highly likely they're making offers like this to boost sales.
If you're planning on listing at Flippa, it may be worth trying a delaying tactic to see if it prompts the discount offer.