Thanks for the post. Maybe a week late for me. Set out on a transatlantic trip on Sept 23, and return on Oct 1. I registered anyway. Years ago I seem to remember MP giving me credit for part of a trip that fell within the eligibility date range, even though part of my trip took place outside the qualifying dates. I'll let you all know if I get anything out of it, but registering cost me 10 seconds.

I agree with other posters. I am so glad to see United do something aggressive to regain some repeat customers. They may actually generate a bit of loyalty.