Originally Posted by
BrianCUnited
Also there is no such thing as a "Republic" flight for mileage earning purposes - this flight is marketed and sold as US Airways Express in this case which is why the MP webpages don't list it. If you bought an AA marketed and sold flight operated by Republic you would not earn MP miles.
This is where is gets confusing. You can fly PHL-CMH on a US flight number operated by Republic and earn MP miles; or you can fly PHL-ORD on a US flight number operated by Republic and not earn MP miles. Fortunately this will all be over in a few weeks before the insanity gets out of control.