I made my ADR's exactly at 180 days, making that June 4. We are arriving December 1 as well. And on a few of my ADR's I had to switch times. They weren't booked solid, I just had to be flexible on my times. Which like 5 minutes is worth getting hyper over

But I would definitely suggest making ADR's for the days you are there. Better be safe than sorry. And like a previous poster mentioned, you could always cancel or change them later.