The commission has reserved its position on ring-fencing of debt to within the areas of the current councils, pending further details from the local bodies on liabilities.
It has asked for the details by the end of next month, after which it will decide whether to form a final proposal, which would then be likely go to public vote in a referendum.
In the last vote on the issue, a Napier-Hastings amalgamation was rejected by voters 15 years ago, with strong opposition in Napier but strong support in Hastings.
Napier Mayor Bill Dalton said while he "personally" thinks it's inappropriate for the councils to become involved in the campaign, Hastings council had "thrown down the gauntlet" and Napier City Council would have to respond - "which it will do in the next few weeks".
He said A Better Hawke's Bay, an independent group of mainly business interests, is trying to influence the public ahead of the commission's survey.
"We are still waiting for the process to be completed," he said.
"They're desperate," he said.
"Now they're trying to run it like a fun fair."