We have a hybrid and it can be considered either/or if you are asking which sites you are allowed to book. We've stayed in a tent loop when we couldn't get a full and it was allowed because we have tent ends.
Having said that, as much as I love the 1500 partial loop, I much prefer a full loop so I don't have to hook up the portable waste tank every 2 days and haul it to dump.
So you are allowed to stay in a partial loop but would probably be much more comfortable in a full. Have a great trip!