In a surprise twist last week, viewers were invited to vote for previously evicted housemates to return to the competition. Shelter, the Teenage Cancer Trust and a third charity to be chosen by the winning contestant are to share 36p from every vote to reinstate evicted housemates, in addition to the 10p from each vote that they were already scheduled to receive from earlier voting rounds.
However, premium rate services regulator Icstis has announced a formal investigation after receiving almost 2,700 complaints from viewers angry that contestants they had spent money eliminating from the show were now eligible to win it.
The regulator may now compel the premium rate telecoms providers - Minick and Itouch UK - to repay viewers the 50p cost of each vote to evict housemates that have since returned, an estimated £3m in total.
A Channel 4 spokeswoman said that charities would be unaffected by the outcome of the investigation, but would not comment on whether they would receive reduced donations.