Flying, on Delta, into ATL on a Wed night, staying overnight at local hotel, then flying, still on Delta, to Cancun on Thursday morning.

Can I check in for the Cancun flight at the domestic terminal ?? or do I have to go to the International terminal.

Will be taking the Sky train from hotel to airport, which drops off a the T concourse end of the airport.

If I must check in a the International Terminal, what is best or quickest way from hotel to that Terminal.

Thanks in advance for all responses, and hope you have a Merry Christmas and a Happy New Year.