Kelso wrote:
At some Caesars/Harrahs properties there is a difference
between the gaming day (which has been answered by other people)
and the promotion day which at some properties can be a "real" day
starting at midnight.
Kelso is absolutely right that gaming day is a can or worms with different hours for promotions, multipliers, bounceback, Diamond-in-a-Day, etc. at the same casino. Bob Dancer had a good article about this but I can't find it now. He wrote about all the possible different gaming days at a casino using the Gold Coast as an example.