I can't answer your question about packages, but I would like to point out that booking separately is usually better (easier to cancel/change) and cheaper than booking a package.
AP rates for deluxe hotels usually come out a couple of months ahead of time, but it varies based on how busy the parks are.
Not sure about the dates either, but 2 things to note:
1. I booked a trip for next September and it was already $300 cheaper than this year's rates
2. If you book a package now and a new deal comes out later on, you can call Universal and ask them to apply that to your booking. Worked for me earlier this year!
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