I dont known whether it is a seized idler. I was just going on what the guy from RAC told me on the side of the rd when he removed the cam cover on the left hand side. He said " most probably a seized idler that has made the belt really hot and been skimming the belt down and its jumped a few teeth and shredded the belt.. You can see one side of the idler that has some decent groove marks on it and plenty of fluffy black stuff all around the cam covers etc.

As far as I can tell it had a new timing belt put on the engine at rebuild. It had a Dayco timing belt sticker that said 46k ish kms from memory. One would assume the idlers etc were replaced...

I don't want to name the rebuilder as its not nescessary... Its not anyone that you would take your subaru to be rebuilt by under choice. They just don't specialize in that sort of rebuild. They are more of a simple 1 or 2 day job sorta place. High turn over of cars and fix things like oil leaks and head gaskets etc... Only reason it was sent to them because it was the choice of the dealers warranty hotline....