How many of these silly threads are we gonna see? Stop failing so hard. Of course it's going to change to a MW, what else did you expect?
It was not his fault, I would have expected the offer to simply get automatically deleted, wouldn't that make sense?
I don't see why the offer should change according to the heirloom, He offered a +2 lhb for 700k, not a +3 one, and common sense suggest me that such an offer shouldn't exist anymore after heirlooming the item instead of changing with it.
I had the same problem about 2 weeks ago,I heirloomed my spirited courser to champion when it was on the market for a spirited destrier, and I immediatly went to the market after realizing that the offer could have changed istead of deleting itself.
Unfortunately it was exactly when the market was closed, so the offer was displayed for something like 2 days and I sent a pm to vargas to remove it before the re-opening of the market and I also reported the bug on irc.
however I was lucky in such an unlucky situation since the day after I logged on irc exactly when chadz said in the chat that he had re-opened the market, so I had the chance to remove my offer before anyone accepting it.
I left another summary of the whole situation written on irc but apparently it still isn't fixed, I hope you'll manage to get your item back speaking with the other player