I did try again, can't access. it display message "There is no Telegram account with the username you provided."
I did comment on Atlant Real Estate Platform Group Facebook and twitter but is not receive answer.
Not sure why Telegram is not working, it's blocked in China, and requires VPN, maybe that's the reason.
Your initial question with Bittrex is really for them, because our smart contract basically sends ATL to whoever sends it ETH. This is why we stated to please not use exchanges as they do not have private addresses.