No, the called-in application for 19m is just that and is completely separate. Even the applicants are different.
The DCO is looking at passenger numbers increasing in 3 phases to 21.5m, 27m and 32m. Maybe the question being asked is looking at the scenario of how many passengers can Luton handle if the inspectors turn down the infrastructure of the 3 phases but allowing for expansion of numbers using an unmodified existing terminal?