The wearer of the tunic had been a 1 Year volunteer in 1912-13, a resserve NCo at mobilisation, and was comissioned at the end of 1914.
He was killed in early 1915.
I had always assumed, with this high collar and no tresses, that it was a tunic he had had altered as an officer...
But seeing the photo above, and the fact it was back with his parents and his Blue one year volunteer tunics... it seems to be very possible that it could have been his prewar tunic from the time he was a one year volunteer? I suppose high colors were not official, but tolerated?