New Year's Eve doesn't give the best lighting and as a result this, one of John's earlier photographs, is not as sharp as it might be.
If the clock in the background is correct, it is still twenty minutes to departure time and it is likely, therefore, that this bus is starting the afternoon shift on this service, with Pontypridd and Caerphilly each working early and late alternate weeks. Three o'clock was the time of the changeover in Caerphilly.