For highly desirable villas (low point villas) they are gone in fractions of a second. You need to wait to actually to the availbility search until 8:00:00.0000001, and quickly hit the "continue" button. If you search too early you will get a "booking window not open error", if you lose the mad dash you will get a different "booking error" message. The second message is not clear, but it should say - "room is no longer available".