A couple of years ago I thought that I would have to transfer to AA, when I was a Premier Exec on United. I ended up writing them explaining how I would like to give them business, along with sending them a copy of my latest United statement showing status and miles.

Within a couple of weeks, I received Gold status and a challenge to fly a set amount of miles (I don't remember the exact amount, but it was really easy to do) and they would up you to the next level.