John Brown, which lost the original pitch to Conde Nast, will now take over the title, which launched as Sorted but changed its name to Posted for the second issue.
Tabitha Miller, commercial director of Conde Nast's customer magazines, has also left the company. The division appears to have suffered since Sue Douglas, president of new business, had an accident several months ago that forced her to take a leave of absence.
Albert Read, the former deputy planning director at Conde Nast International and business director of Conde Nast Asia-Pacific, who took up the newly created role of UK general manager last month, is overseeing the day-to-day activity until Douglas returns next month.
Christian Price, group ad director for customer magazines, left the company last month to join the Wall Street Journal Europe, which signed a joint venture with US publisher Doubledown Media to publish Trader Monthly, previously co-published by Price at Conde Nast.
Emily Rowbotham, previously travel manager on Conde Nast's glossy Tatler, has taken up his role.
The loss of the account leaves Conde Nast with just three accounts - House of Fraser and upmarket hotel chains Maybourne and Mandarin Oriental - but it is still pitching for new business.
In June, it lost the Harrods contract to River Publishing, while high street retailer Littlewoods has also put its magazine, previously published by Conde Nast, up for pitch and is understood to have drawn up a shortlist.
The publisher launched Sorted in February. Unlike many customer magazines, the contract stipulated that the Royal Mail would review its performance on an issue-by-issue basis. Royal Mail and Conde Nast declined to comment.
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