This earning change is probably listed elsewhere, but I thought this updates comment of existing rule by tods27...
As of 01MAR18, M&M <K booking class> (Not booked on "016" United ) will earn 25% base miles plus UA elite tier bonus.
With UA, one must ticket all flights on "016" stock to earn PQD - Premier Qualifying Dollars.
- Craig
Thanks! My cheap K fare just got 25% better . . .