(04 Feb 2014, 4:26 pm)Dan wrote 3941/42 (TEN/Metro Radio) are both spare vehicles for the "TEN" network.
3943 (Red Arrows) is a spare vehicle for "Red Arrows" service X1, and has a tendency of being used on Saturdays on the X88 if not required by the X1.
3962/65 (Angel) were both originally spare vehicles for "Angel" service 21, but service changes designed to improve reliability saw the PVR increase by two.
3963 (Tyne Tees Xpress) is a spare vehicle for the "Tyne Tees Xpress" network.
3964 (Children in Need) is a spare vehicle at Riverside depot for any service.
BIB: 3962/5 have always been part of the PVR since the B5s arrived, given the first entered service mere days before the service changes happened (while 3962/5 returned to use around the time of the change).