Telecom New Zealand's outage-prone XT network has claimed its second scalp in as many days with chief transformation officer Frank Mount resigning today.
The news came amid calls for Ministerial intervention over the technical issues that have dogged the next-generation network.
Mount's resignation was effective immediately. He had been in the role for 18 months.
"In the interests of our customers, our team and New Zealand, I have regretfully accepted Frank's resignation," Telecom NZ chief Paul Reynolds said.
"I am pleased to announce that CIO David Havercroft will assume the responsibility for all network and IT operations from today and CFO Russ Houlden will carry interim responsibility for our Shared Services operations and Technology Strategy."
Mount's resignation came just one day after Alcatel-Lucent - the vendor that built the XT network - revealed its NZ head Steve Lowe would be replaced.
In a statement, Alcatel-Lucent said Lowe had "decided to leave the company".
He would be replaced by Jyoti Mahurkar-Thombre, the former general manager of the vendor's Next Generation Networks product unit.
"Jyoti has more than 20 years telecommunications industry experience, and has driven next generation network rollouts for many of the largest and most progressive operators in the Asia Pacific region and around the world," Alcatel-Lucent's Asia Pacific president Rajeev Singh-Molares said.
"She understands our customer's priorities and we are looking forward to her personal contribution to better serve our customers in New Zealand."
Singh-Molares had previously said Alcatel-Lucent would "do whatever it takes" to resolve the XT network issues.
The Opposition has renewed calls for New Zealand's communications minister Steven Joyce to intervene.
"The time has well and truly come for the Minister to get involved. Steven Joyce needs to seek assurances that the technical issues Telecom is having and are being addressed to seek a permanent solution and are not just being patched up every time XT fails," spokeswoman Clare Curran said.
"He should also encourage Telecom to communicate with and compensate its customers who are understandably fed up.
"The patience of XT customers has run out and the lack of public confidence in the mobile network requires Steven Joyce to ask some frank questions of Telecom management."
Telecom said last week that recent issues with the XT network, which heavily impacted users located south of Taupo, were "due to traffic surges in the network overloading the Radio Network Controller in Christchurch."
It was unclear whether the latest issues - resolved overnight - were related to the same kit.
Reynolds said last week that Telecom planned to install two new controllers by "mid March".
It had attempted to migrate 20 cell sites to a new controller last week but was forced to roll back the migrations when "problems and service degradation" continued.
Telecom chief executive Paul Reynolds was due to front the media later today.
Stay tuned to iTnews for full coverage of the event from Auckland.