Sorry for the delay, I failed this recipe several times, 1/ because I broke the pastry case after precooking it and 2/ because on the second attempt my sister burnt the pastry case while precooking it :) :) :) We still made it though and ate it, but well...
Anyway, the author I think messed up with the apple types instructions, because he says to purée the Bramley and layup the 4 Cox apples, but this is way too many apples for layering + later in the recipe mentions layering Golden Noble 8-/
So the first time around I used Jazz and then had the idea of alternating Granny and Juliet for the apples on top without peeling them to have a green/red effect, but on top of a burnt pastry the taste was a bit lost.
On the second attempt, I had run out of apples to alternate, so I ended up actually using Golden for purée-ing, Granny for layering, and Jazz for the "toping" which is actually a caramelized sauce type thing.
This worked really well! Everybody loved the cake that way :) I will keep in mind all of your advice to continue experimenting with different types of apples :)