However MTOWs can often be increased during freighter conversion
and, for amplification, if the intended scenario involves shorter range, on a medium to longer range hull ... where MZFW becomes limiting .. rescheduling the fuel usage can result in an STC to increase the MZFW to the point where MLW becomes the limitation more often than not .. which can help the payload materially over a shorter sector operation ... eg Ansett did this with the Electra passenger to freight conversions many years ago as a lot of the operation was shortish range (Australian east coast) ... generally TOWs were comparatively low (and the bird went like a cut cat - chaps ought not to be allowed to have so much fun) .. but then we would head off to NZ or similar at max gross (around 52T if I recall correctly) and the old girl tended to be a bit of a dog.