Ken has indicated either on this thread or the other one that he enlisted in the Militia 16 1 1908 as 3133. His age was given as 18 yrs (no months)
His record reads
5th Bn Attested 13 1 1908
Joined Depot 17 1 1908 - 5 3 1908 (49 days)
Joined Lanc Fus 6 3 1908
Going to Paul Nixons excellent Army numbering site
http://armyservicenumbers.blogspot.co.uk/2009/07/lancashire-fusiliers-regular.html1305 joined on 19th August 1907
1486 joined on 11th May 1908
1793 joined on 2nd January 1909
2015 joined on 8th February 1910
Therefore 1400 looks a nice fit for March 1908 I'd say.
(Read the blog to understand why such a low number was allocated in 1908. They had had to start all over again from 1 in about 1903)
{ Whilst I remember , where is he in the 1911 census? Should be in a barracks somewhere. }
Him being a Regular Army man explains why he went to France within a couple of weeks of outset of war.
Him being a Regular Army man explains this quote of yours
" His discharge certificate says that he served 11 years and 1 month with the colours and 11 months with the reserve. "
That is to say, in 1908 he'd have signed up for 12 years (5 with colours, 7 with Reserves or is it the other way round) The war of course interferred with his time on Reserves if indeed he went into Reserves
The reason I asked about his date of birth was because there is a G Ritson with the date of birth 4 8 1896 and an RE post war number in the list of files held at the MoD. I now realise it cannot be your George not least because he'd have been 8 yrs old enlisting in 1908!