NEA chart, page-17

My guess:
I would not be surprised if they have numerous US clients already signed up or close to signing up and are waiting until they have a predeterimed number before making an announcement. Maybe an announcement such as "Nearmap secures its first 1000 US clients". They will likely make an announcement late in June so the market can not complain about little or no US revenue in the full year accounts released in August. That gives them until the release of the half year report in feb before the scrutiny on US revenue will start. By then they will likely have 1000's of US clients.

Anyway, imo this will be all academic in a years time. The US market is approximately 14 times the size of Australia. As in Australia, they have no direct competitor in the US with the same successful business model. I see no rational reason why the business model will not succeed in the US as it has in Australia.