There were no obvious signs of unease among Reform UK’s top team on the first day of last week’s conference in Birmingham. It was the party’s first ever “business day“, an attempt to project a sense of seriousness about economic policy by gathering a few dozen business leaders and some members of the press, with the general public excluded.

Prospective chancellor Robert Jenrick joined various panels to explain his proposed remedy for the UK’s lack of growth. Housing spokesperson Richard Tice unveiled a radical proposal to deregulate the planning system and cut business rates for SMEs. At 8pm, guests sat down for an “exclusive private dining experience”, paying £395 per plate to engage in “strategic dialogue” with senior Reform figures.

It was at this dinner that the phones of these senior Reform members will have started pinging. An investigation by Channel 4, aired at 7pm and picked up by the BBC’s 10 o’clock news, had secretly filmed Nigel Farage and two of his closest aides in a pub in Clacton apparently suggesting how to circumvent electoral law to secure a £500,000 donation from a man posing as the son of an American businessman. Reform had been notified of the programme a few days earlier and had reportedly been unconcerned. Farage’s long-serving right-hand man Dan Jukes, one of the aides filmed in the investigation, had looked relaxed on Thursday afternoon as he mingled with the assembled business people on the conference floor.

By 2.30am Jukes, who had described himself in the footage as Farage’s future chief of staff in government, had stepped down, as had the other aide Reform’s head of policy James Orr, pending the outcome of an internal investigation by the party. Throughout Friday, as thousands of Reform supporters flocked to Birmingham’s National Exhibition Centre for the main day of the conference, the controversy dominated the national news agenda. Farage attempted to play down the footage as “injudicious pub talk” by a pair of “contractors” while a carefully planned series of headline-targeting policy announcements were left in disarray as the party’s senior team were forced to field questions about Reform’s fitness to govern.