Yeah that sounds like about when ours calmed down too. I'm a teacher, so my Macks have been around lots of people as well and they're always just as well behaved as our corns and BPs at least. We actually use our GTPs for educational animals too because of how calm they are. The only ones I'm not comfortable with all the time are our brazilian rainbows....they'll bite anything within reach even as adults!
Honestly I think that ours wouldn't even be cage defensive if they were in something with more front-end visibility...I'd probably bite too if my roof suddenly lifted up and a big hand came in after me.