Can't book Premium Plus with partner leg?
I'm looking at flights that have United + LH group leg, but United.com shows PP unavailable if the flight includes legs on an LH group flight even though the UA segment has PP (e.g., book USA-FRA PP available; but USA-FRA-xxx it's not). Confusingly, for some itineraries PP is available, but not for others (e.g., an earlier connection it's not, later connection it is). Understand that the LH group flight doesn't have PP, so it would be mixed cabin anyway . . . but any tricks to allow such a booking?