They're not doing much in the trailer line either. I think perhaps they're hoping not to get very large viewing figures so that they can justify ending it. If they won't change their minds (and keep giving us views of the North York Moors and coast!) I think they should at least produce a Christmas special to round things off nicely. When this series was filmed the cast and team didn't know that it was going to be the last one (so I read, anyway), so it's probably a 'left-up-in-the-air' episode, which would be very unsatisfactory.