I just wrote to Ida to find out about this. In 2007 the tartan was designed and registered and on the Scottish registration site it says that Dalgliesh is the (I can't remember the exact word) weavers of this tartan. Meaning they were listed as "the only ones who are supposed to". I think it is left over from that run .
I need 10 meteres for what my client wants. My new order could only be woven in 10 oz. or 16 oz. (I was told) I would be a little miffed if there were some on a shelf in back somewhere....but I think it was just left there, sort of what the Scotweb site does, which for example, has the Maine Dirigo tartan listed in weathered and ancient etc. and it has only been woven in modern (as far as the people in Maine know)
I will let you know what they say. Thanks barb for looking