>>537860137
>He literally tells Piccolo he kept up with his training when Piccolo ask at the start of the movie.
He did not. He just says he hasn't lost his edge once Piccolo elbowed him.

>nothing says Gohan couldn't go Ultimate anymore in the movie, he just didn't go ultimate until it was needed.
He was getting beaten up by Gamma 1 and Piccolo had to pretend he's hurting Pan for Gohan to go Ultimate. If Gohan could transform on his own he would have done so.