"Frankly I'm not comfortable not giving you a forecast - I'd rather give you a forecast," he said. "But to have a forecast ... where there's a risk that $30 million of that revenue gets carried over four days and shows up in the next [financial] year .... these are very material things," he said.
Ferrier said investors would understand that the board's decision was "the prudent thing to do".
"I guess on the other hand we provided an enormous amount of financial information for investors."
Fellow software developer Gentrack, which listed in June, was forced to downgrade its profit forecast just five weeks after the float as a result of delays with major customer contracts.
Auckland-based Orion plans to sell between 21.9 million and 29.1 million shares at $4.30 and $5.70 apiece, raising between $125 million and $155 million, the bulk of which will be new capital, according to its prospectus. That would value the company at between $720 million and $915 million by market value.
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Alongside the new capital chief executive and founder Ian McCrae selling up to $5 million into the float. Existing shareholders are estimated to keep between 82.6 percent and 86.3 percent of Orion after the float.
The new funds will be used to accelerate the company's research and development capacity for new opportunities in the management of patient healthcare, improve the implementation and delivery capability, and provide additional financial liquidity.
A final price is expected to be set on Nov. 7, with a dual-listing on the NZX and ASX scheduled for Nov. 26. The offer opens on Nov. 10 and closes on Nov. 21.
Orion's revenue grew to $153 million in the year ended March 31 and while it has been profitable in the past, it's not currently because it is reinvesting most of its cashflow back into global expansion.
The company is forecast to post a loss of $14.8 million in the six months ended Sept. 30, 2014 on sales of $80.5 million. Annualised recurring revenue, the favoured sales measure of software as a service firms, is expected to rise to $52.1 million in the first half of the 2015 year from $44.2 million as at March 31.
The software developer has reinvested most of its recent cashflow into new hires, with total staff numbers now at 1,100 worldwide. It has achieved high growth rates ranging between 25 percent and 30 percent for many years and has previously said it had a target of hitting $1 billion revenue by 2020. Some 90 percent of revenue is derived offshore.
- Additional reporting BusinessDesk