About AEON wallet maintenance on Bittrex exchange... I found this:
"There were some large reorgs/forks in June 2017, like on the order of 50 or 100 blocks, the cause of which was not clear. Prior to that there was a bug that required a chain rollback, which resulted in delisting from cryptopia exchange. After these incidents the maintainer of aeon GitHub repo, smooth, requested bittrex to take the wallet offline until aeon could be updated to a more recent monero codebase. That process still hasn't been completed, so the wallet is still offline."