Hello David, and Welcome to TalkingScot,
It sounds like he may have enlisted for seven years full time followed by five years in the reserves and hasn’t included the reserve period in the total. Perhaps he left the UK not long after the full time duty had expired and that’s why. If he was in the UK in 1914 and still in the reserves then presumably he would have been called up at the outbreak of war.
http://www.1914-1918.net/recruitment.htm
Ancestry has surviving British Army WW1 records but for anything prior to that it would be best to check what’s at FindMyPast, although they mainly seem to be pension records. Perhaps if he was still a reservist with the British Army during WW1 his records may have been with those that were bombed in WW2. Maybe the Ancestry ones would be worth checking as well.
The 2nd Battalion of the Royal Scots were stationed in India for many years. According to regiments.org they returned to the UK in 1912 and went to France immediately war broke out.
http://web.archive.org/web/200710141735 ... /001-2.htm
They appear to have actually left India in 1909. The Times of India (New Delhi) reported on 17 February, 1909:
“The hired transport Dongola, Captain H. Powell, will sail to-day for Southampton with the 2nd Battalion, Royal Scots and details, comprising 70 officers, 23 ladies and 11 childrens; 13 warrant officers, 14 women, and 20 children; 1,076 non-commissioned officers and men, 65 women, and 98 children.”
(Note that the officer’s wives weren’t women and the soldier’s wives weren’t ladies.)
Hope that helps,
Alan
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