It really is more about her client work - she might be qualified for 6 years and have seen 20 clients a week in that time = lots of experience. She may have qualified 6 years ago, saw 5 clients a week and taken two lots of maternity leave = much less experience. I'd go to her for a few sessions, schedule a review every 6 weeks or so and see how it goes. If she feels she's getting out of her depth there are options open to her to support her or ultimately she may decide you're at a stage where you need more than she can give but she may already have a lot of experience under her belt.