If I have two home resorts but want to plan a trip spending time in each, do I have to call 2 different times for reservations, or can it all be done at the 11 month window with one call to MS?
It would be two separate reservations. So you would have to call 11 months out from your start date at each resort. And when you make your ADRs, you'll have to do the same. When stay #1 ends, so does your ADR-making. You have to wait for 180 days from the start of the second reservation (or 90, whatever the time is now).