Originally Posted by
findark
I believe there was another similar report where the buyup price includes implicitly reticketing another segment in a lower fare class.
That was me, and it was the same deal - K class one way, P class the other way, and it was done without telling me half my itinerary was being "downgraded" to a class ineligible for GPUs
It was fixed in the end, but it took some agent heroics to pull it off and preserve my GPU upgrades in the other direction.