I’ve never been able to get FOP at 60+1. Usually takes at least 60+3. For June I could not get it at 60+ 4. I get them for only two people. Larger groups would probably be harder.
That being said, I was able to get FOP as a 5th fastpass when I was there last week for two. My cousin did, too.
Last Monday, I got it for my 4th and 5th fastpass.
If I had to go on 60+1, I’d say odds are better of getting it Day-of than 60+1. That’s been my experience.