I guess the day men carry all sorts of parcels for clients.. as required by NTA. I think you're also required to provide reasonable assistance loading/unloading the same. If changing a wheel in accordance with OEM recommendations on a very odd occasion is beyond your physical limitations I guess one could question your fitness to operate a SPSV. However, while our cars are subjected to test after test after test the fitness of persons operating said machinery gets no attention whatsoever.
I never considered whether the bottle jack would fit under the jacking point, Octy... probably 'cos I don't carry it with me. Unfortunately it's too cold to try it now but I might do so in the future should I remember. I guesss a trolley jack is considerably less versatile than either the onboard emergency jack or (if it fits) a bottle jack, particularly in operating the same in close proximity to a kerb?