If John survived army life & was discharged, all his records would be with his attestation & discharge papers, these would include details of where he was thro'out his army career, with all details of punishments, promotions, & medals awarded, place of enlistment, & physical description. These records are where I stated in my post., the National Archives, Kew.
He may well not have been in England for any census after 1851, the Crimean War was 1854-1856, if John was in a Scottish regiment he could well have involved as there were many Scots & Highland Regs. there.
I think the first thing to find from the Nat Arch. would be which regiment he was in, that would make it easier to track him thro' the years.
Meliora