(11 Mar 2016, 7:27 pm)Kuyoyo wrote 36/37/38 all interwork so no, not rare (plus all the 'Zone' Enviros have 'Middlesbrough-Hartlepool' and 'Middlesbrough-Norton' branding on the side)
Ah right.
The whole 'zone' thing isn't too easy to follow from afar.
Seeing a vehicle with Hartlepool included in the branding and not going anwhere near the place threw me.