Apple identification help.

[Nik Saunders]

Hiya, we have an apple that we have not a clue what it is. The parent tree was an old tree in a neighbour's garden in Vendee, France that we took a scion from and grafted onto a tree here at home. It is defifnitely not an eater or a culinary apple. It was in an orchard with other cookers and eaters though, one russet I wish we'd taken a scion from that was huge, like a Howgate Wonder, but I digress.

The apple itself is small (but not so small to be a crab) and ripens late September (now) to an almost yellow colour with pink blush. It is sweet, probably bittersweet, with soft-ish tannins and quite juicy. it seems to be rather a heavy cropper every year so far, we've only had it cropping for around 8 years. The scion was grafted onto an established MM106 tree and has been vigorous to say the least.

It is quite distinctive to look at as you can see from the photo. 

Thanks in advance, Nik.