I'm assuming you are talking about the Frozen Ever After Illuminations Dessert Party? They are notorious for not releasing the dates until sometimes just a few weeks beforehand. It's not available every night, so hopefully you will luck out and it will be available the night you're wanting, but I wouldn't be too worried yet about it not being loaded in the system.
We went to it at the end of August and totally felt it was worth it. Everyone's opinions on these sort of things will vary, but we really enjoyed being able to sit and relax at the end of the night while waiting for Illuminations to begin. The view was excellent, right along the water. There are a few tables a row back from the water, bit still with a great view. You have a table preassigned to you that you can sit at as soon as you're admitted to the party and you can stay sitting there throughout the show, so that's a huge perk in my book. The food options were good, nothing that will blow you away, but I felt there were plenty of options from dessert to fruit to cheese fondue. There were a few NON-alcoholic drinks that my kids enjoyed, as well as several alcoholic ones (all included). There was never a line for the food or drinks when we went and everything was just so relaxed. The tables didn't feel crammed together. There was a photopass photographer that came around to tables to take your picture if you wanted. Everyone received a pair of special glasses that you could watch the fireworks through that made the lights turn into a different shape (I can't remember if ours were flowers or snowflakes). Then after, everyone lines up to be taken to the ride. On our night, the Frozen ride was down so they took everyone to Soarin instead. Some people in the group, myself included, didn't want to ride Soarin (we had a toddler that wouldn't have been able to ride). CMs were there to work with each group on alternate arrangements. For us, we were given a fastpass for later in the week to ride Frozen which seemed perfectly reasonable.
If you have any other questions, I'd be happy to answer.