It's not specifically gluten free in M & S. Their normal stuff just happens to be GF IYSWIM. It's all lovely, have ordered the lot from there this year as we are on holiday till Christmas Eve so I didn't want to faff.
We're gluten and dairy free which can be a bit of a faff.
Got a gluten free Xmas Cake and Xmas pudding by "The Village Bakery" at local health food shop. Haven't done pudding yet but by look of what is left of Xmas Cake DH is finding it pretty yummy.
Also got gluten free mincemeat by the Foods of Athenry from there. Make toasted sandwiches with Genius fruit loaf in place of mince pies for DH. also stuff a baked apple with it and this morning layered some with a sliced bana for him and heated it up in the oven as a breakfast sweet hot treat as he had an early start.
Got some amaretti for me as I don't really like dried fruit and they are christmassy especially dipped in melted chocolate bit like a florentine enough for me. Booja booja truffles also fab. Especially th ehazelnut ones, though I have got DH some caramelise dbanana ones as he likes bananas so much I call him a monkey sometimes
The shop is great- it's called Realfoods and they will deliver orders over £24 for free by next day courier. their deadline for xmas delivery is midnight on Sunday. Huge gluten free/dairy free range .I used to use the service all the time when we lived in the Scottish highlands and it always got there on time.