Rocket Lab is on the verge of announcing a contract to launch satellites into space as it works on a new schedule for the test programme.
"We're now fully booked for 2017-2018 and we're continuing to book more customers.
"The growth has been very strong," said chief executive and founder Peter Beck.
He could not reveal details of the new customer - which will be in addition to Nasa and a company that will send probes to the Moon - but said the company was rapidly stepping up production of its Electron Rocket.
The full-size rocket has not yet done a test flight and Beck was disappointed not to meet that target of a trial lift-off at the end of this year.
"A number of things have transpired that mean we're not going to make that," he said.
"Some from our end - technical - but the resource consenting process has delayed the build of the launch site quite significantly and that has pushed us out into flying next year."
It has shifted its launch site from near Christchurch to Mahia, south of Gisborne where it is about to break ground at the tip of the Mahia Peninsula.
"They're very motivated to bring Rocket Lab to the area. The site is a much simpler site from a resource consenting perspective being much more remote." It was still pushing on with consenting its Birdlings Flat site on Banks Peninsula and, as part of a deal with Nasa, had options to use the US agency's launch sites in other countries.
Beck said the Mahia farmland site was a logistical challenge as the rockets could not be manufactured at a centre nearby but would be taken there nearly complete from Auckland in a container.
Staff were being recruited for site works including a concrete pad, a launch tower for the carbon composite rocket and a hangar. Satellite dishes and other communication equipment is also being installed.
The company has started recruiting people, including for a project manager to oversee the construction of the site.
The engine on its Electron rocket uses small high-performance electric motors and lithium polymer batteries to drive its turbo pumps. The engine will also incorporate parts made by 3D printers to cut costs and speed up the manufacturing process.
The 16m Electron is about a third the size of average rockets it will compete with to take satellites into space and is designed to slash the cost of launches.
Beck said big tech companies, including Samsung, Canon and Google, were now interested in getting satellites into space.
"That's a whole different deal. If Samsung say they're going to put internet in space it's going to happen, there's no if, buts or maybes," he said.
Rocket Lab's financial backers include Silicon Valley venture capitalists, Sir Stephen Tindall's K1W1 investment fund and Lockheed Martin. It has received up to $25 million of government funding over five years.