Although the drop down menu for online reservations lists three times, I believe that only covers all the options given throughout the year, meaning whether wishes is scheduled for 8, 9, or 10pm. When I booked ours, wishes was scheduled for 10pm. The earliest time offered for that night was 9pm. Now, there are some offered later times such as between 9:00 and 9:15, but I do not recall anyone ever mentioning anything later than that.
From what I have researched however, everyone, regardless of reservation time, are let in one hour before wishes, with preassigned tables.
Reservation are generally available 60-90 days prior, depending on what time of month you are looking at. Generally the entire month opens up on the same day, in the afternoon, so if you are looking at the end of a month it could be almost 90 days out. I booked May 24 on March 7, the first day available to book.