As I suspected from your previous photo, the pellets have disintegrated too much to be definitively identifiable - however the woodland location would tend to rule out short-eared owl, which tend to be found in more open land, and the time of year rules out long-eared owl, which are only summer visitors to the northeast of Scotland. I think barn owl is also unlikely, as even in their disintegrated state the pellets look the wrong shape. This also rules out little owl.
This leaves tawny owl as the best likelihood - however your observation of the scale of the pellets (not visible through the photographs) might disprove even this. If the pellets were any more than 4 inches long at most, this suggests one of two things, as tawny pellets seldom get much above 3 inches in length.
1) That they belong to a feral Eurasian Eagle Owl
2) That they are the scat of a Red Fox which has weathered and fallen apart to a point that they are no longer in the diagnostic shape, and fur and bone has been revealed within.
