The rule for all resort parking is that if you have a table service reservation, you are supposed to be granted access. For counter service, shopping, etc., it's been a bit hit or miss for people. In either case, you are granted 3 hours access only (as they don't want people parking at resorts to go to the parks). It seems that a major factor regarding access is how full the lots are. In this regard, WL generally is more open than a Poly so your odds are better but not guaranteed.