I have a John SYKES born 1838 in Witcham. In the 1861 census he is a Private at the Chatham Barracks, Kent. I know that he married Rachel HARVEY in 1857 and had 2 children George in 1858 and Charles in 1861. (I also know his parents, so don't need any help there

) I haven't been able to find them after 1861. However, I have recently found a newspaper article 27 Sept 1862 which says:
"DESERTER - John Sykes, of Witcham, was charged upon his own confession, with being a deserter, and was sent to prison. The authorities of the War Office will be written to"
Cambridge Independent Press. (Sept. 27, 1862)
Is it possible to find which prison he may have been sent to, and whether any records exist? How long would he likely be in prison?
Any help most appreciated.