It's always scheduler approval if I'm not mistaken. At least with me. I've don't probably a dozen shops for them over the last 4 years and I think I've always gotten 10/10 or maybe 9/10. I almost always get a shop if I am only applying for 1, I rarely get all of the shops I apply for if I apply for more than 1, unless they are remote. I've always assumed they get a lot of applications and prefer to spread the shops around to multiple shoppers.
There are reasons that a body stays in motion
At the moment only demons come to mind