He is passionate about his country and devoted to the idea of having an officially accepted flag which reflects it.
But he doesn't particularly like the one we've got.
"It's time for a change," Mr Mills said.
He said the Union Jack, which took the main stage of the present flag, was no longer relevant and not representative of this country.
He said too many young Kiwis had served and died under it.
"We are our own people now - we live in the South Pacific," he said.
While his father was a Londoner who had strong links to Great Britain, he did not.
"Any flag would be better than what we've got at the moment."
Mr Mills said he veered towards something based around the koru design and reckoned designer Andrew Fyfe, who has put forward the koru as the centrepiece, is on to it.
"Because it is very distinctive and simple."
He had perused the line-up of flags in the referendum but was unsure which he preferred.
The simple black-and-white koru needed some red in there, he said.
He was also keen to embrace the Southern Cross.
However, he said he was not holding his breath for seeing something new which had the official stamp of approval as the flag of New Zealand.
"People need to stand up but I don't think there will be a change - I'd like to see a new flag but I don't think we'll see one."
Mr Mills said Kiwis did not tend to display a lot in the way of national awareness in terms of flying flags.
He had spotted only six or seven flying from houses around the city.
He said he would continue to fly his.
"Although I would like any other [official] flag up there instead."