Anecdotally a friend of mine chose Southwest over United a few years back because he was going to give up flying WB planes just to get based in DEN and being a Captain, because he was told it was 20 years to hold Captain at United in Denver and only 10 at Southwest. He’s an FO based in Denver for Southwest and he’d almost be a line holding Captain right now if he had taken the United job.

I asked him how soon he would upgrade to Captain and he said its not even close yet.

You just never know.