In that case it was definitely booked to call. Sounds like it was only advertised at New Barnet.@ yorkie
Had no idea of the debate I would initiate!
I was on the 1054 from Hatfield this morning, which would have reached New Barnet around 1108 so seems it probably WAS booked to call there after all. My mistake
The additional call was not announced on the station information displays or on-board the train, though. I guess the people at New Barnet knew in advance that they had an extra London-bound train, judging from the numbers who boarded!