Thanks for all your investigating, Judith.
I have done quite a bit on Orlando over the years. The 'Homer' place of birth referred to in the service record of the Orlando you found (and the one I thought was 'mine' is possibly Domer as in Chilthorn Domer, again misheard).
The 'new' documents in the British Army Service Records on FMP appears to disprove that the infantryman is not my forebear but a Royal Marine. My Orlando is the one born in Yeovilton and died in 1853 in Plymouth.
If he is a Royal Marine I need to check the description book to confirm place and date of birth.