AA comped me Platinum from DL GM a few years ago. My travel agent worked with her AA sales rep to make it happen quickly and with no hassles. If you have one, or a corporate travel coordinator, I'd suggest enlisting him or her to help the same way.

My comp came in April, about a third of the way through the qualification year. My DL travel for the first few months was history. AA said they'd give me any level that I had two-thirds the miles for. As it happened I ended the year with about 55,000 AA miles, enough for Platinum with no favors but below pro-rated EXP, so I didn't have to see if they meant it, but you can ask for a similar promise. Get it in writing, or confirm it to them in writing, since people can move between now and year's end.