Looks like it's fixed now, mine has come back online. If you can get some at the current price (75) then I think you'll do alright. Reckon you might get 20 or 30% return in a few days. Well that's what I'm hoping for anyway

I got the info direct from the ArtByte forum, not Bittrex. Bittrex aren't the best at replying to issues  I think it's to do with ArtByte changing code and moving to SegWit, but I'm no cone head so don't quote me on that

According to their support staff, Bittrex is still in the process of upgrading the wallet and is clearing transactions.