Sunnybunny, all airlines from time to time use 3rd. party carriers for various reasons, such as a tech aircraft. This is just a sub-contract on an ad-hoc basis. I seem to recall that Flybe did lots of work for AF and had some of their own aircraft painted in AF colours. BA do the same, just look for the 'operated by' label painted somewhere on the fuselage.
This is not the same as MANX2 which was posing as an airlines but in reality was little more than a travel agent.
The comment that the general public should think about who's up the pointed end, is very pertinent.