I would just ask. Just say that you'd feel more comfortable right now with more frequent check-ins for a few weeks and even that you feel like you need to develop a relationship with her more quickly than usual due to circumstances. I did that when I started with my therapist because I knew the transition was going to be hard (my prior therapist moved to Europe with pretty much no notice at all; 3 weeks after she said she was leaving I was meeting the current one for the first time and a week after that she was gone. This turned out to be good because he is a much better fit for me but at the time it was devastating).

It's not like she's going to be mean to you . I get seen at a reduced rate and my therapist actually doesn't get anything for seeing me so I always feel bad when I need to see him twice a week but he just tells me that the fee thing was his decision and it is fine. It's still not my favorite thing to do, especially if I know he is busy and I'm taking up appointments that he could earn money but it's been the arrangement for a long time and he insists it is fine so I go with it.