It has to be at the start, sounds unhelpful but work on how she starts her pitch.
She is in control, slow down and get in rythem.
I call that a "Gym Step." Some girls develop it when they are pitching in a gym or on a hard floor with no hole in the front of the pitching rubber to get their toe into to push off from. Sounds like she needs to focus on getting loaded and moving forward sooner. Video would help.