Did same day last night. Same day is upper terrace with lots of tables and just the pastry desserts. But all same days are welcome to go to the lower level for additional drinks and sundaes, but they can't stay or sit down there. They must come back up to their level. Different colored wristbands identify.
All same days are escorted to Plaza viewing area, but you do not need to be escorted and can come and go as often as you like. They just check for your wristband at the Plaza entrance. After dessert I left and rode Peoplemover and then came back for the shows.
I spoke with a supervisor prior to the above and she confirmed all of my questions.
Advance folks are not told about Plaza, but it was confirmed they are more than welcome there too.
Same day was great last night. Lower level was packed but upper maybe only 20% of tables used. And Plaza was great! Very uncrowded, everyone sitting on ground, tons of room. Felt like a picnic. A LOT of envious looks from the crowd.
Desserts IMHO aren't worth it. You're paying for the parking on this deal.