I made my ADRs online last week at the 180 day mark. My recommendation would be to log in and make sure you are all set to go - even do a dry run the night before. If you are staying on property, you will have to enter your reservation number. Once you've done that, it is a matter of waiting til the system rolls over - I tried consistently from 5:45 til I finally got in at 5:58 or so. Good luck!!