The appointment marks a return to the drinks retailer for Armstrong, who previously held the role of trading director before leaving in May 2003 to become purchasing director at rival retailer Unwins.
Armstrong replaces Tim Luteijn, who has vacated the role to pursue other interests outside the company. However, Thresher Group said that Luteijn would be supporting Armstrong in an extended handover period over the next four weeks.
Armstrong takes up his role this month, reporting to Stuart Higgins, Thresher Group’s supply chain and buying director. Higgins said: “David’s knowledge and expertise within the sector will stand us in good stead as we develop our strategy.”