Getting hired was a piece of cake, since I've been an independent professional writer/editor for 30+ years. But I did have to submit materials I'd previously worked on and as I recall (this was awhile back) I had to revise something they submitted to me, for their approval.
The big pain here were constant changes at the editorial end. Apparently the in-house people are not (or were not) well-paid or something else was haywire. In just a few months time I went through three or four different editorial contacts.