That's great! It's so nice when they can let themselves in and out. Then you can just relax and watch them.
I've got a question for everyone. This morning our youngest pullet, maybe 13-14 weeks old, was singing a LOUD egg song! We searched all over for an egg and found nothing, but just in case we uncovered the nest boxes and filled them with duff. Does the song mean eggs? She has gotten pretty big lately, but not 'wide' in the hips like the older girls. Her face and comb are still yellow too. I expected it to be one of the other girls singing when we heard it but it was definitely her, just strutting around singing her little heart out. The others were standing around petrified because they had never heard it before
No other egg-type behaviors except this song, except pink faces on most of the girls and the light brahma doing a pseudo-squat the other day. We're out of eggs so maybe she is just waiting for us to go buy some...
My big rooster sings an egg song when I scare him.

I'd definitely guess that she's just talking for the sake of it. None of my girls laid until their comb got really red. With all of them it happened really quick over a couple of days.