Hi,
I found this "1865 JAMAICA ALMANAC" which shows which miltary were in Jamaica in 1865 which includes the 2nd Battalion, 6th Royal Regiment.
http://www.jamaicanfamilysearch.com/Members/a1865_08.htm
Also, a long read but interesting, written by Thomas FAUGHNAN, Late Colour-Sergeant, 2nd Battalion, 6th Royal Regiment. It contains the dates of when and where they were in the relevant time period.
https://www.gutenberg.org/files/51595/51595-h/51595-h.htm
26 Feb 1858 "we proceeded by rail to Aldershot"
18 May1858 "from South Camp to Farnborough Station, where we took the train for Portsmouth." + "embarked on board H.M Ship "City of Manchester"
25 May 1858 Arrived Gibraltar
25 June 1862 embarked H.M.S. Himalaya.
26 June 1862 for the island of Corfu.
01 Jul 1862 Arrrived Corfu
This man was then stationed at Santa Maura.
04 Mar 1864 H.M.S. Orontes for Jamaica, in the West Indies.
18 April 1864 Arrived Jamaica
01 April 1867 Embarked on board the "Tamar" for Cork.
09 May 1867 Arrived at the Firth of Forth
"The 2nd Battalion 6th Royal Regiment was stationed in Edinburgh Castle over twelve months, when they got the route for Aldershot camp on the 30th May 1868."
So John YATES would have been in Jamaica and then back home in 1868.
Regards,
Daisy
sorry Daisy for the long delayed reply as i missed this message originally.
John Yates was in the 6th Foot Regiment{which I believe is light infantry or at least it was according to this ...
''The Royal Warwickshire Regiment, previously titled the 6th Regiment of Foot, was a line infantry regiment of the British Army in continuous existence for 283 years. The regiment saw service in many conflicts and wars, including the Second Boer War and both the First and Second World Wars.''
John Yates was listed as a Staff Sergeant according to his son Edward John Yates Birth and Marriage Certificates{but John Yates was listed as ''Deceased'' when Mary Ann Yates shows up as visiting her cousin Caroline Kirk in Manchester back in April 1871 - meaning listed as a widow}.
John Yates married Mary Ann White on 3rd November 1868 in Wembdon, Bridgwater, Somerset {John Yates father William Yates is listed as Deceased but Mary Ann White's father William White was listed as still alive at the time of their wedding}. their witnesses were George White and Maria Beatrice Beil.