France 1914 Cover, 1er Groupe Aeronautique. Assistance Needed.

Good evening all.
At our local flea market yesterday I came across this interesting little cover (amongst a few others!), and would appreciate any help with it. As you can see it carries no stamps, and is postmarked Versailles SRP. I understand this to refer to the current Paris-Saclay-Versailles airport which is 6km south-west of Versailles, used by the French air force as Toussus-le-noble aerodrome from 1907.
So first puzzle, why does the postmark read as it does?
The cachet is another puzzle - is it free postage for servicemen? The wording is 1er Groupe Aeronautique, Le Conseil Administration. The figure on the cachet does appear on various official cachets on google.
Problem with all this guesswork on my part is that the postmark date of 1/8/14 is prior to embarkation of the British Expeditionary Force, which happened two weeks later. So, is this a blank cancelled envelope given a pencilled English address at another date, or could it be right? If so, what British involvement might it reflect?
As I say, any light that can be shone on this little find will be gratefully received.
Regards
DavidR

I have no idea what it is, but it's a neat little piece.

I was thinking the same thing Cjd

A couple of links, in French:

http://albindenis.free.fr/Site_esca...litaire6.htm

https://www.memoiredeshommes.sga.de...he.php?fam=4

The French military aviation was made up of three groups in 1912. The 1st group was located in Versailles.

This might be a military franking used by a British aviator serving with the first group.

https://www.asoublies1418.fr/index....2&Itemid=108

Versailles was the préfecture of the Seine et Oise department.

Park Place is a country house in Berkshire, near Henley on Thames (Oxfordshire).
https://en.wikipedia.org/wiki/Park_...e,_Berkshire

At the time, it was the property of the Noble family.

Thanks Bobby. A quick look at both links doesn't hint at any British involvement at the time in question.
I have found the addressee (sort of). The address is Park Place, Henley on Thames, Berkshire. Park Place is a mansion bought in 1870 by John Noble, a manufacturer of paints and varnishes, and stayed in the family until 1947. So Mrs Noble would have been the lady of the house at time of writing.
By the way, there is no receiving postmark on the reverse of the cover.
Regards
DavidR

Thanks NSK. I hadn't considered a British pilot being with the French prior to the BEF embarkation. But I guess quite a few young fliers would have made their own way to the action at the start of the war. Trying to find out now if that person was a young family member.
Regards
DavidR