I would expect that they would be reluctant. If it did accept standard barrels, and you could use a standard AR setup to change barrels soon everybody would be changing them. That's not an issue. But sooner of later you know somebody would get caught with a 12" or 14" barrel on a "supposedly" non-restricted rifle, and the RCMP and the CFO would be all over them. All of their work and money that was invested to get a non-restricted status would be put in jeopardy.
I can't say as I blame them. I wouldn't want anybody messing with something that I'd assembled to meet certain criteria.