Foxconn did not provide further details. Its executives were quoted as telling Reuters that full production would resume between late December and early January. The ongoing supply disruptions at Foxconn's campus in the city of Zhengzhou were costing Apple roughly $1 billion a week in lost iPhone sales, Daniel Ives, an analyst at Wedbush Securities, had told CNN Business. He estimates that Apple is short of between 10 million and 15 million iPhones in the vital holiday shopping season. The troubles started in October when workers left the campus because of concerns about working conditions and shortages of food. Short on staff, bonuses were offered to workers to return. But protests broke out last month when newly-hired staff said management had reneged on their promises. Workers clashed with security officers, before the company eventually offered them cash to quit and leave.