The exchange is the only one that can fix that I'm assuming  Maybe someone else knows more about this issue... But from what I gather Bittrex was not supposed to remove the wallet anyway citing their policy is removal only after 14 days.. which is why I suspect Bittrex is going to re-list XHC (as they hinted at such when I emailed them a few days ago) and they are possibly putting everyone's coins @ Bittrex in the new wallet... The only one who can confirm that is Bittrex so I don't think they would destroy anyones coins 7 days beforehand... All I can suggest is you open a support ticket with them (Link Provided Below) Incase you haven't done so already and wait for their response. The responsibility lies solely with the exchange here respectfully.

https://bittrex.zendesk.com/hc/en-us/requests/new