Ah well, my initial idea didn't stand up in court. I accept @aptaim's comment that 'administration' inherently contains an element of supply and 'supply' (as defined in the Regs) does not apply.
I'm reviewing the other relevant Provisions of the Regs to see if anything negates the interpretation used by ambulance services. I've not found anything yet...
If this interpretation is not negated then it opens up a spectrum of opportunities for administration of non-parenteral POMs by a range of persons operating within a regulated service under local protocol.