First off then:
Born 1971
If born before 31st August of that year would have started school at Easter 1976 ( most probably, assuming he went to a state school). This would be Infants school. If born after 31st August then would start September 1976. Let's assume he was born before 31st August. Reception, Year 1, Year 2.
September 1978 he would move up to Junior school. Year 1, Year 2, Year 3, Year 4.
September 1982- Secondary School. Year 1, Year 2, Year 3. Then start O level/ CSE exams. Year 4, Year 5 sit O level exams in June. So now it is 1986.
September 1986- continue into school's VIth (6th ) Form or go to 6th Form college. Lower 6th, starts studying for A Levels most likely he would do 3 possibly 4 of these. They would be sciences, certainly Chemistry and Biology, as he is going to carry on into studying medicine. Upper 6th, sits A Level exams in June 1988.
September/October 1988 he goes to University to start studying as a doctor. This will take 6 years.

Hope that helps with this part of his education. Our system here has changed a bit since then so what I've given you will be authentic and accurate for the time. I'm assuming he was educated in England as the system in Scotland is, and always has been, completely different.



If you want/ need any more detail on this part please ask.

I get the impression John probably signed up later, maybe even at Uni when he was studying to be a Doctor, perhaps there was one of those careers stalls and he thought "ooh, well that's something interesting and exciting I can do with my medical degree..."

Anyway, this is my chronology. I've worked backwards, starting with when he meets Sherlock in 2010, so I don't think he could have been born in 1971, even if he took a year out between finishing college and starting Uni...it would mean there'd be a few years missing in his life. I'm still working on the basis that he is older than Sherlock though...and Sherlock can't have been born any earlier than 1976 because he was a teenager during the Carl Powers case (which if my memory serves me correctly was 1988):

1974 - Born
1985 - Start secondary school
1990 - Start college/sixth form
1993 - Finish A-Levels.
1994 - Year out
1995 - Start Uni
2001 - Finish Uni
2002 - Working as a Doctor
2004 - Sign up for Army
2005 - Deployed to Afghanistan
2009 - Return from Afghanistan
2010 - Meet Sherlock (Yay!)