Originally Posted by
pumical
Is there any risk of loosing my miles on the return leg if UA puts me on a non UA flight irregardless of the circumstance (weather, mechanical, etc.)?
You can request the original routing mileage if you so choose. Simply fax in a copy of the original itinerary or e-receipt along with the ticket number. Also, include a note that you wish to have credit for the "original routing." The fax number to mileage plus is listed in the UA forum FAQ.
You will get RDM's or EQM's.
You will only want to request the original routing if-
1) you were re-booked on another non-star alliance carrier (search double dip for more information)
2) your new re-route did not earn as many RDM's or EQM's
When on MR's I highly advise that you have your laptop handy with a copy of the most current United Electronic Timetable. This timetable is updated every Saturday. Be prepared to generate your own routings to get home and be prepared to present this routing (and a couple of others) to the agent at the airport.
YOU HAVE TO DO YOUR HOMEWORK. It will make things go a lot smoother.