With an Ivatt 4MT running tender first was this a regular working I wonder?
Peter Kerslake says "Hunstanton was at the end of the line from Kings Lynn and the line's usual motive power was nothing larger than the 'Claud Hamilton' 4-4-0s.
This is a train of formidable length , loaded far more heavily than any I recall seeing on this line from my days at Kings Lynn, and with a most unusual combination of motive power, with B17 61642 Kilverstone Hall from Cambridge at the head so perhaps it's a special working or excursion to the coast at Hunstanton".