Cremeegg, not at all unreasonable of Junior79 to be trying to transfer the mortgage after selling the property it was originally secured on. This was one of the much publicised features of this product, the fact that you could transfer it from property to property without redeeming it.
It is a complex product and there is no doubt that very few UB personnel have any clue about it, your best bet is to find some of the original First Active lending staff which are still in some of the UB branches or in Head Office. There is someone who posts on the banking & finance forum on Boards that is obviously an employee of UB and seems to know the product very well, I have seen them answer several detailed questions about it before.