Port of Tauranga chief executive Mark Cairns said they would probably handle another 2000 containers as a result of the rescheduling.
"While that's good for the port and region - to have all of the extra work going on - it leaves a sour taste in my mouth and I don't think it [the strike] is good for New Zealand. It's our exports that need a productive and efficient port and if we can't deliver on that ... we will go backwards."
About 4700 containers are said to be impacted by the strike and Ports of Auckland is estimated to lose up to $1.2 million in revenue.
There were currently talks between the Port of Tauranga and and Ports of Auckland concerning local support during a proposed second strike over four days next week.
"We will help as best we can but we won't disrupt our existing customers. They are fixed," Mr Cairns said.
He said the port wanted to minimise any impact on imports and exports.
"We are lucky we have a very good pool of labour and that we can deal with these things. We are lucky we have a great workforce."
Ports of Auckland chief executive Tony Gibson said mediation talks with the union were unsuccessful and if the situation continued there was "significant risk" the ports could lose a shipping line service entirely.
Mr Gibson said if the proposed strike next week went ahead it would affect a further seven ships and as many as 7500 containers. "This is a very serious situation."
The action involves 327 of 580 employees.
Mr Gibson said the company agreed to meet with the union for further mediation next week.
Maritime Union of New Zealand national president Garry Parsloe said Mr Gibson had no one to blame but himself.
Although port workers were locked out and would be losing pay, union members understood the long-term importance of maintaining terms and conditions.