According to the check-in staff, the notice was on the site when I reserved online, but the only indication I found was the fine print in the 'Terms and Conditions,' with no clue what the fee might be.
We arrived at 3:00 and were told that even though rooms were ready, we would need to pay $35 to get our room an hour early. However, a new policy was just instituted (September 24, 2023) that checking into the hotel before 4:00 requires a fee based on card play. This was our fourth stay at this casino hotel, and aside from the 'dumpster incident' a few stays ago (we were above the dumpster area and the crew decided to power wash the area at 10:30 pm!), we enjoyed the resort and the lovely tower rooms.