Young Rider

Hello, I have just joined this forum because my daughter, age 11, has started cycling more seriously. She has done a few kids triathlons and is making the jump to a Sprint Triathlon in February. Her Grandpa has purchased her an awesome bike, a Specialized Dolce Elite, and she is very excited to rack up some miles. She is also a competitive swimmer, training 6 days a week, aproximately 4500 - 5000 meters a day. She runs 2 or 3 days a week, 2-3 miles. My question is, how much riding should I allow her to do. She has 4 weeks until her Tri, bike leg 10 miles, but I really want to avoid overtraining. So far this week, she has done 3-4 miles, four times and would have done more if I had let her. I have looked at Sprint Tri training plans, but with her high swim training volume, none of them seemed appropriate. My thinking is: Week 1, 4-6 miles x 3 , Week 2, 6-8 miles x 3, Week 3, 8-10 miles x 3 and the week prior to race, 3-4 miles x 2-3. Does this sound reasonable? I welcome all comments and suggestions. I am a swim coach and have no experience with cycling.