(09 Apr 2014, 8:30 pm)Tom wrote Isn't it just the 81 now?

No, since February it's been split back to the 81/81a (except the opposite way round - previously the 81a was the Stokesley service that diverted via Lakes Estate to serve Redcar Hospital, now the 81a is the short journey as far as Guisborough which operates via the Green Lane Estate at Redcar East railway station and avoids Kirkleatham)