As you will note when reading that thread, use year is not relevant to when you can go (anytime of year) or when you can call to reserve (allways 11 months out at home resort and 7 at others). Its importance has to do with being able to bank points if you have to cancel and to assure you can do that most suggest that you get a use year that begins shortly before time you usually go annually.
As to availability at 7 months it depends on time of year, resort and type of room/view. AKV concierge and value, BLT standard view, and BWV standard and boardwalk view are often difficult, as are treehouses at SSR. BCV and VWL as smaller resorts can also have some periods where they are more difficult than other near park resorts to get rooms. All of Oct, first half of Nov, Thanksgiving time, first two weeks of December, Christmas week and a few days before and after, 5 nights (Thurs through Monday) for Marathon weekend in January, Easter weeks, and time around July 4 can be difficult for any near park resorts (BCV, BWV, BLT, and VWL) and the first week of December, Christmas week, and the second of December (the number 1, 2 and 3 in that order highest DVC demand weeks of the year) are usually impossible for any near park resort and even AKV and OKW can be present some difficulty. SSR is always wide open at 7 months out except for treehouses. In fact, SSR is usually wide open well beyond the 7 month window. Studios fill before 2BRs which fill before 1BRs..
Also be aware that "calling right when the lines open up" may sometimes not be fast enough because the 7 month window opens on-line at 8 a.m. an hour before the phone lines open and some things can actually fill up between 8 a.m. and 9 a.m. before anybody can make that first phone call. In fact, I have seen things like BWV standard, AKV value when they happen once in a while to be open at 7 months out disappear within minutes after 8 a.m. So if you are not exact in doing an on-line reservation as soon as the clock strikes 8 eastern you can be out in the cold.
