If you're making your adrs online, I believe you can make them anytime you want. I don't think it's not like buying concert tickets online wheere you have to wait for a specific time (I'm not trying to be flip or anything, just making a comparison is all).
I made our adrs a couple of weeks ago and my suggestion would be to have some back up restaurrants in case you can't get into a place you really want. If you don't get what you want the first try, one a few minutes, then try again. That's what happened to me for one restaurant I really wanted. I am guessing someone cancelled.
Have fun making your adrs! Really makes your trip feel that much closer!
right but on your 180th day does it start at midnight (like in 15 mins) or at the same time that the phone lines open? And what time does the phone lines open?