No, just the logical solution to an oddball set of four units which are difficult for EMR to diagram. XC have 38 4-car units.
It’s also unclear if a new Operator would want 23 5car units and 4 7car units. Probably a case for altering to 19 5car and 8 6car in 2024 (when they transfer Operators). Could even be more reformed as 6car if another operator wanted some 4car units. A few 4car might be good replacement for GWR shortened HST sets
Without going to far off topic, cross country could do with a fleet that has more capacity, but less than double units on some routes, so a fleet of about dozen 6car might suit them.