I imagine true Midsomer Murder fans in the UK knew in advance of the cast change but in the USA, we're at least a year behind the most current British prime productions. Our public broadcasting stations (PBS) operate independently throughout our vast country on almost NO funding. That means that viewers often don't get to see Masterpiece Theatre or other wonderful BBC productions until they are perhaps 5 or 6 years old or more! Probably, the licensing fees are less by then. Of course, PBS stations in large metropolitan areas like Boston, New York, Chicago, and Los Angeles are not as financially constrained. I live way up in the upper left corner of the USA. I typically see things 10 years after they been filmed.
I had heard that there would be a cast change via media rumors but that was years ago. Meanwhile, MM episodes continued as ever. Then suddenly there's a new DCI (which is fine; people really DO retire in REAL life). My issue is that this was not addressed within the series except as a slight afterthought. Changing the face of the person the camera focuses on 90% of the time is important enough to warrant at least a subplot or a single scene! I had trouble rapping my head around 'this new guy' as hero when the old DCI fit like my favorite pair of jeans. A person who really LOVES a series, creates (in their own mind) an idea of who each character is. Having a suitable transition allows the TV audience to bid farewell to the outgoing character and say hello to the new.
Aside from this gripe, there is an incredible improvement in the production value of the series in general. I'm very impressed by this aspect. I also thoroughly like Neil Dudgeon so much but really miss John Neville. I wish he would return occasionally just to schmooze cousin to cousin.