Suppose that a year or two before the outbreak of WWII, a British shipbuilder/designer takes inspiration from aircraft carriers, and ambitiously develops a design for a MAC that they think might make them more relevant in the next war. Once the war does begin, the design gets dusted off and presented as a vital supplement to merchant shipping protection or convoy escort against surface, submarine, or aerial raids.
Presuming that this finds some backing, and more importantly the pilots and aircraft can be found, what are the effects of increasingly numerous MACs protecting British convoys by 1940? This obviously isn't a replacement for actual convoy escorts, but even a little air cover or scouting could certainly improve the efficiency of protection in the Atlantic.
Could this have much effect on shipping losses, or is it just an interesting gimmick without substantial impact on the Battle of the Atlantic?