On the B747-400, in fully automatic mode, the systems know the landing elevation courtesy of the FMCs. Once established in the cruise (so it thinks you will continue to destination) it adjusts the cabin altitude as a function of deltaP
and landing elevation.
In a normal flight to a low elevation airport, the cabin altitude will be controlled by deltaP, and be typically below 6000ft for the initial cruise, rising a little as you step climb.
Flying, for example, to Mexico City, the landing elevation will control the schedule and when established in the cruise, the cabin will be scheduled to destination elevation.
This means that the cabin crew end up pushing trolleys around at an enhanced elevation for all the cruise.
As caring pilots we used to manually set the landing elevation to override the FMC until approaching ToD, at which point we would return control to the FMC and an increase of cabin altitude would result in time for touchdown.
This system worked very well.
Then a numpty manager got involved and instructed that the automatic pressurisation schedule must not be over-ridden
