I think it's so they can run 5 car formations during peak instead of 4 (God forbid if the 3 car unit fails). Should have ordered them as 2, 3 & 4 car sets.
I'm not sure if the stock numbers add up to allow that many 4/5/6 car 195 workings (not that I've crunched the numbers, however). And many Northern stations too small for a 6-car service presently won't fit a 5 either. SDO is a workaround in places, but not universally.
The lack of corridor connections is baffling from a revenue collection point of view, but I wonder if either the corridor connection design wasn't available from CAF in early 2016, or Arriva's order has had to be so basic and no-frills that the cost of connections would have pushed the provincial envelope too far. While no slight on CAF's build quality, any new stock going to Northern would almost inevitably come courtesy of the lowest bidder.
It'd be nice if modified cabs could be retrofitted with connections later, but there's not a chance of that. It'd either be a cascade of non-gangwayed 195s to lesser routes, or - more realistically - make do as is. Plus the 195/331 cabs look very ample from a driving perspective, and I wouldn't get far trying to take those away from drivers!
If CAF were able to make inroads with a bimode 195/331, especially one interworkable with the stock on order, they might just find a use. Even a 90/75mph top speed on diesel could be sufficient.
