I originally booked MAD-MIA-CLT-LAS...2 tickets on 2 PNR...1 in in J MAD-MIA and the rest domestic first. The other MAD-MIA in Z, and the rest domestic first. They changed both tickets to MAD-PHL (J) and PHL-CLT-LAS in domestic first without my permission. I called and had them refund the 12.5k extra miles paid for the original Z booking one way since they changed it to J. The other one was not impacted mileage wise, but both had the routings changed. The original flights and flight numbers still exist for booking (I checked with a test revenue booking) although the times have changed. I still do not know what the reason was that they changed my 2 original bookings and no one gave me any answer.
They are RT though, and begin in C1...these legs are the returns that were at issue. No changes were made to original outbounds, which were LAS-DFW-JFK-MAD, both in J.