Adding to the Flock.

That’s a trick question   
I’ve had chickens in the tops of trees, but they kinda flap from branch to branch more than fly. 
Is Dora exploring where she shouldn’t?

It was Dora!
She flew onto the top of the old run which is made from 6' high wire netting with a top rail for rigidity. She them flew down and ran/waddled to her new run - looking as you do, when you're desperate to get to the loo. I opened the run door, she rushed in and into the nest box, breathed a huge sigh of relief and laid an egg.