Looks like I'm one of the lucky ones!
I dropped it off yesterday first thing at the local Ford Dealership (not even the one where I bought it) with a note mentioning the smell and that there's a TSB about the PTU. I asked them not to do any work without contacting me first because I wanted to try to get it covered under the warranty.
Not a word until 4:00pm when they said: 'Your car is ready, we replaced the parts under your Powertrain warranty, you can come pick it up by 6.'
Didn't charge me a dime and also gave me a clean bill of health on their '20 point check up' or whatever that is where they check the tires, breaks, oil and fluids and stuff.
The receipt says which parts were covered and mentions the TSB they did the warranty under.
No muss, no fuss. Now I guess I'll wait to see if the problem returns but I was really glad it was part of the 5/50 powertrain deal because it means I've still got a year and plenty of miles to see if it comes back.
Thanks everyone!