Running 26 minutes early, 66510 passes Kings Sutton on 6 October 2021 with the 3J04 09:17 Aylesbury to Banbury Depot (via Marylebone and Stratford-upon-Avon) Rail Head Treatment Train. 66519 is bringing up the rear. Early October seems a little early to start the RHTT season, as hardly any trees have started shedding their leaves.