I am not any good at charts but for GV's throughout the year:
WDW Resorts:
BWV: during WDW's high DVC demand season that runs from late Sep to marathon weekend in Jan, the BWV GV's sometimes fill at or a little before 11 months out and, except for stray days here and there, are usually filled before 7 months out. During WDW's low to moderate demand season that runs from the Monday after marathon weekend to late Sep, BWV GV's are typically filled for 2 to 4 days per week by 7 months out, but sometimes can be found open for a week at 7 months out, e.g., that actually happened today, Dec 9, when this morning you could have reserved the GV for a week for July 9-16 (July after about July 7 is one of the lowest DVC demand times of the year)
OKW: the GV's in the near Hospitality House booking category have a real risk of filling at or a little before 8 a.m. at 11 months out throughout the year (only the BWV and the hospitality house OKW GV's have an 11 month issue at WDW). At 7 months out they are seldom available except for an occassional stray day . The other GVs at OKW are usually missing two to five nights per week during the high season by 7 months out but are often open at 7 months out during the low to moderate demand season except for times in June, mid-March to mid-April, race weekends (the Princess half marathon weekend in February is the highest DVC demand time during the low to moderate demand season) and around holidays.
SSR: through 2016, the SSR GV's have been invaribly open throughout the low to moderate demand season, and are usually open during the high demand season except for a risk otherwise during some extremely high demand times: Columbus Day weekend to the second weekend after it, the Wine and Dine Race weekend in early November, the last weekend of Food & Wine in mid-November, the Tues though Fri of Thanksgiving week, the first two weeks of December, Christmas week (more so a risk around NYE), and marathon weekend in Jan. Beginning 2017, there are now low cost standard and high cost preferred buildings and thus patterns might change. Thus far, through mid-July 2017, both have been open at 7 months out, although the standard GV has been filling somewhat quicker than preferred once you get beyond 7 months out.
AKV: during the low to moderate demand season, Kidani savanna view GV's are invariably open at 7 months out; the standard view GV's (there are only two) are also open most of that time but sometimes fill before 7 months out and one cannot pinpoint a particular time or reason that happens because it just seems random. During the high demand season, the standard GV is usually gone three or more days a week; the sav view GVs are usually missing days during those extremely high demand times mentioned above but are sometimes open, even for a week, otherwise. The Jambo GV's are typically missing three to six nights during the high demand season. During the low to moderate demand season, they are open about 60% of the time with holiday times, June, parts of May and Aug, and race weekends often having days missing.
BLT: both lake view and theme park view GVs are usually gone 4 to 7 days a week by 7 months out during the high demand season. During the low to moderate demand season, they are similar to the Jambo GVs, with one or the other, or both, being open about 60% of the time and both being gone for the other times.
VGF: open at 7 months out during the low to moderate demand season. Usually gone two to five days a week at 7 months out during the high demand season except that one can sometimes find 6 to 7 days in a row open outside the extremely high demand times.
Poly: though they are not Grand Villas, the 2BR Polynesian bungalows are considered to be in the same class as high end villas at WDW. The Poly bungalows are still developing patterns but currently they have been filling at a pace a little quicker than SSR GV's, and are open at 7 months out during the low to moderate demand season and often during the high demand season except for a risk of filling some days before 7 months out during the extremely high DVC demand times. When Poly gets close to selling out, the bungalows may tighten up for availability some, particularly during the high demand season.
Non-WDW Resorts
Aulani: standard view GV's often fill throughout the year at exactly 8 a.m. at 11 months out and are seldom avalable at 7 months out other than for a stray day or two. Ocean View GV's can fill for some days per week before 7 months out during Aulani's two highest demand times of the year, Christmas week and June 8 to July 6, but otherwise they are typically open at 7 months out.
VGC: no problems getting a GV at 11 months out. They are very often gone at least two and usually more days per week by 7 months out during the year and invariably gone for race weeknds and the D23 Expo weekend before 7 months out. Best chance to possibly get them for multiple days in a row is during non-holiday and non-race times from January 3 to the Thurs before Memorial Day.
Hilton Head: GVs do not disappear at exactly 11 months out at 8 a.m. but during the summer season (Memorial Day weekend to Labor Day weekend) an occassional day can sometimes disappear fairly quickly once the 11 month window opens. During that summer season they are often gone for three to five days per week at 7 months out. For time of the year before the Thurs of Memorial Day weekend, and the time of the year after Labor Day weekend, they are usually open at 7 months out except multiple days can fill per week for holiday times and the non-holiday periods from mid-March to mid-April.
Vero Beach: the GVs on occassion disappear at exactly 11 months out particularly during the summer season (Memorial Day weekend to Labor Day weekend), and are very difficult to get during that time at 7 months out except for possibly two to three days in a row once in a while. From Jan 3 to about mid-March, they are usually open at 7 months out except for the holiday times, when multiple days can be gone. Mid-March to memorial Day weekend, they are typically gone three to six days per week by 7 months out. After Labor Day weekend through about mid-Oct, the GV's are usually gone two to three days a week by 7 months out. Thereafter, for the rest of year except Thanksgiving and Christmas time, they are usually open at 7 months out.
