Last Summer my T was gone for 2.5 weeks. We didn't arrange any kind of replacement, I wasn't doing too well but T wasn't realizing that. After about a week I had panic attacks severe enough to make me reach out to my GP. I had never seen that doctor before. Somebody else at the same clinic had referred me to my T and they had a file on my mental state (which contained a 3 page letter by my T that explained my diagnosis and our therapy together).

I was very glad to have somebody to talk to. It was never therapy, but it felt good to even just have a human connection somehow. The first time she hadn't read my file and just asked about what was going on, I mentioned being in therapy and having a lot of anxiety. She asked me about coping strategies I had discussed with my T as well as some short questions about my experience, where I didn't really have the impression she 'understood' what I was talking about but it was like talking to a good friend who just listens. She printed out some pages on crisis intervention offers in my city, tried to call a therapist to schedule something for me and when that didn't work asked me whether I wanted to check in again after the weekend.
Then I had two more short meetings with her, where she'd read my file and asked some questions related to that as well.

I felt it really helped. It wasn't as long as therapy or as intense or helpful or anything like that. But it kept me from freaking out completely.