you should be able to withdraw them,
coinomi wallet seems to be the option most people concider as an easy option,
also you can, of course download our wallet at europecoin.eu.org.

i would not recommend to let your coins remain on bittrex.
Given some wallet changes are part of our agreement when returning to bittrex in 90 days,
i could not think of any reason for them to keep the old wallet indefinetaly

have fun
Matthias


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