The three year old battery is a Banner Starting Bull 12v 30Ah 300A (EN) with bar code 005753040717.
that's the correct spec battery and still used by Morgan
Has anyone experienced the same problem?
yes, loads of people
Will the push start have damaged the exhaust emission control system?
not likely. i did it a few times a year ago when i had the same problem.
i think the main concern on starting is the valve and cam system which have variable compression for starting.
as i say i don't think it really matters.