No, that was in my japanese art. Wing Chun doesn't do that, I want to reconize other's rank in whatever art they come from. It's only polite.
In my old art the blackbelt kept rank, but still started to learn with the white belt stuff. Politics, I guess, just kept their "stature" or rank in class.
ex. one girl came over to JJJ class as a black belt in TKD. She still had to learn the "new" style from the beginning, but was reconized for her rank.
We had a guy come to our WC class from another WC school, he'd studied there for 5 years. We accepted his "rank" with other teacher and started him with "our styles" basics. he was allowed to skip a couple of grades, so to speak, but not to the level he was in other teachers WC. He just didn't know what we taught, it was different. So we started teaching him from there (grade 2) but from other teacher he was a senior student. We treated him as a SiHing/senior student, but had to get him up to level with our Si-Je/SiHing senior students. Which took about 6 months, but he was too stiff. so, it's really all relative.
Basically, give respect for the hard work and training they've done in other arts and from other teachers, just start them new with what you teach.