Eskom Holdings, South Africa’s monopoly power utility, shuffled some senior managers weeks after missing its own target for restricting power outages.

Bheki Nxumalo has moved from his position as head of generation to the post of a group executive overseeing new projects and will be replaced by Rhulani Mathebula, Eskom spokesperson Sikonathi Mantshantsha said on Tuesday, without giving reasons.

Daniel Mashigo is moving from his position as general manager of primary energy to head up Eskom’s Cluster 2 of power plants, replacing Mathebula, Mantshantsha said. The primary energy position will be advertised. The changes were announced in an internal statement from COO Jan Oberholzer.

Eskom exceeded its winter target of only three days of power outages last month as a number of units at its mainly coal-fired power plants broke down.

Since taking over in January, CEO Andre de Ruyter has made a number of changes and appointments. Richard Vaughan, the former chief financial officer of bankrupt retailer Edcon Holdings, was appointed as treasurer in May and Caroline Henry has been made chairperson of the Eskom Pension and Provident Fund. Stephen Meijers was appointed COO of Rotek Industries, a construction and transport unit of Eskom.