Large numbers of holidaymakers put the Central Otago cellphone system under pressure yesterday, shortly after New Zealanders had sent millions of phone text messages on New Year's Eve.
Delays were experienced in making cellphone calls between Dunedin and Wanaka early yesterday afternoon.
Telecom spokeswoman Sarah Newcombe said ''intermittent connection issues'' had resulted from overloading and ''exceptionally high volumes of traffic'' rather than a ''technical fault''.
There had been particularly high volumes of cellphone traffic in several key Central Otago holiday areas, such as Wanaka, Queenstown and Alexandra.
Problems had been intermittent and had apparently not affected large numbers of customers, but she apologised for any disruption to service.
Telecom had increased cellphone capacity in holiday areas, and was monitoring the situation, she said.
Vodafone officials said its customers had experienced only ''minor congestion'' in Wanaka, and there had been no complaints involving other parts of Central Otago.
Vodafone officials said that on New Year's Day, between midnight and 1am, customers sent 3.7 million text messages- more than twice as many as in a normal hour, and up on the 3.1 million sent in the corresponding period the previous year.
On New Year's Eve, Telecom customers sent 7.8 million texts between 6pm and midnight, compared with 8.8 million for the corresponding period in 2011.
