Adding my experience:

Fourth year NK FO. Like Spirit but interested in Legacy A for personal reasons, basing one of them. Began applying to Legacy A, and also Legacy B, in March. Close to 1500 hours SIC on the Airbus. No TPIC though as I never upgraded at my regional. Didn't hear anything from Legacy A until October. Have never heard from Legacy B.

Interviewed at Legacy A this week. I think it went alright but I think I could have done better on the technical scenarios. There were eight other pilots in my little interview group. There were zero regional pilots, and only one military. Three of us were from ULCC.

Yesterday I was talking to one of our pilots, not that much junior too me, who has a job offer from Legacy C. In his interview group of 20, 10 were military, 5 were regional (all captains), 5 were non-regional civilian. Everyone was hired except the regional pilots.