Hi, not sure if it's the right topic to ask that question. But according to
this NEM forum page Bittrex hasn't confirmed yet if they will support the XYM Opt In and Distribution. I have XEM on my Bittrex Acccount so I wonder if I have to withdraw them to get the XYM airdrop.
Sure I could ask Bittrex Support directly but they are slow if they answer at all.
Was the snapshot taken yet? I've searched a bit and I found some results about it being postponed. So if that's the case, you can simply withdraw the funds to one of the exchanges that are going to support the airdrop, and wait until they distribute XYM to their users.