Moving up now in age, DD will be playing 11x11 on the larger field per U13. Unfortunately, with a birthday in Dec, she is also the youngest on her team

She's about 5 foot 1 so she's not too small but a lot of her peers are taller/bigger than her being a year or so older.
Was just curious how transitioning play to U13.. what helped/would help a girl get ready for 11x11 play? Do the girls play for a much shorter time on the field?
She also moved up to a pretty strong team level for the Fall so will be a new team she is on. I'm a bit nervous because of that too..
She plays striker but sometimes wing/midfielder. In the past, they liked to play her defense too but really offense is where she's been hugely successful in comparison and she enjoys the striker position. She's crazy psycho fast, but her speed is not endurance based - it's just that ability to zoom when she wants - she told me it comes when she really wants to get to the ball in specific situations, she can just be so Fing fast. She runs fast too but it's different to see on the field between when she's running and zooming LOL Her coaches say she's pretty strong technically although I don't really see it but I don't play soccer either

I think in practice she's technical but on the field, I feel like she could really improve her reaction times. By her own mission, she doesn't really dribble that well..
Just curious how her speed may be affected and what to watch out for transitioning to 11x11 larger field.