This means this person probably has been in the business for a while and is lucky enough to have several regulars. She doesn't -need- to take new clients, maybe because she has a civ job.
I don't see how this is a new trend, I think she's perfectly entitled to only want clients who will come back. I just don't know how she can make sure that by a new client will become a regular. However I've heard that in Ontario and other places it's a lot easier to find regulars.
It can be a lot more pleasant to see regular clients you know you get along with, specially if you're risk averse. I love meeting new people but there's always a risk in this industry.
It's totally understandable for escorts to prefer seeing the same men all the time honestly. It's about safety and like she says building a connection. When you see the same person several times you know what to expect, intimacy becomes easier and you have more to talk about.
The question I'm asking is : did she publish this before or after seeing you?