I'm pro pref interview against flows.
Are people who are 1500 deep into an airlines supposed to wait for the 1500 guys on top of them to be offered jobs at mainline before they have a chance to go?

Pref interview still gives special consideration to those at the connection carriers but doesn't hurt the career progression of everyone else.

I know we have a seniority based system in this industry but choosing where to work shouldn't be seniority based. I still think the Mainline interview is the last barrier in making sure someone is a good fit for a place.