The group, which includes brands such as Topshop and Dorothy Perkins, had said 23 shops were to shut across the country as part of a plan to rescue the struggling business.
The extra closures are detailed in the small print of a company voluntary arrangement, an insolvency procedure which Sir Philip hopes to use to cut staff, slash rents and reduce the company pension pot in a bid to save the wider group from collapse.
“Due to the intensely competitive environment, [Evans and Miss Selfridge] will reduce their retail store portfolio significantly in the short term,” the agreement proposal says, while also adding that Sir Philip would be willing to consider selling parts – or even all – of the business.
Arcadia currently has more than 560 stores across the UK and Ireland and employs some 22,000 people.
Under the proposed restructuring announced earlier this week, it would shut 23 stores and reduce the company's contribution to the pension fund by £50m a year.
Ian Grabiner, the group’s chief executive, said the action was "tough but necessary”.
But before the plans can be put in place, they must be approved by landlords, creditors and the company's pension trustees.
On Friday, MP Frank Field, chair of the Work and Pensions Committee, wrote to Sir Philip suggesting he had a moral obligation to use his own money – much of which he has extracted from Arcadia – to support the pension fund.
The new blow is just the latest in a series of calamities for the 67-year-old tycoon, who was reported as no longer being a billionaire in March.
Last year he was embroiled in claims – strongly denied – of racist and sexist bullying and harassment towards staff.
Before that, he was criticised in parliament over the demise of department store BHS, which collapsed leaving a huge pension deficit a year after he sold the business for a pound.