I know it's become a favourite cliche on this site, but I envisage there will be renewed interest in the class 442s once they start on the Portsmouth route.
Yes, I suspect that the Transpennine class 68s will come in for some scrutiny and become one of the main highlights of the loco-hauled scene from this year onwards.
While the mark 5s are not slam door stock of course, I would think that a half hourly frequency of loco-hauled trains, worked by powerful diesel locomotives with traditional names and little or no passenger mileage to date, over a scenic route with notable gradients, that is recalled with fondness for the Newcastle - Liverpool loco-hauled services that operated until 1990, and has a good choice of pubs en route, will be appealing to many.
I certainly expect to have more than one crack at it, and it is fortuitous that it fits neatly into my sporadic long distance travel patterns. I can't wait for them to get started. And enthusiasts in the north of England will need some way to get their local loco-hauled fix now that the Cumbrian Coast class 37s have gone.
HST's aren't exactly being withdrawn either. They will live on with GWR, XC, EMT and Scotrail for sometime yet.
Yes, I suspect there will be an increased number of Scottish holidays for those with a fondness for HSTs, as the country will become the prime bastion of continued HST operation. The same can be said to a slightly lesser extent for EMT services until presumably around 2023/24, and all bets are off as to how long these two fleets retain their slam doors and droplight windows as an added attraction.
I'm not convinced that they'll be around for much longer, I'm certain the next EMT and XC franchises will be replacing them!
Should have another four or five years yet then. Wabtec might have just delivered the last of Crosscountry's five power door fitted HST sets by then!
Once the HST track muck-spreaders have gone (or have had their sanitary arrangements brought into the 20th century), are there any other classes of rolling stock similarly (un-) equipped, - other than heritage LHCS?
At present, most of the Sprinter fleets, although these are all being fitted with retention tanks as they go through PRM modification (Some TOCs' class 158s had already been retrofitted).