Mr Janes was appointed deputy chairman of ACC last year in a boardroom sweep-out of the state-owned insurer.
The resignation of a director, announced on Friday, could be the first move in a pre-IPO clearout.
First-half sales rise up to 5% but profit may be similar to last year amid little New Zealand growth and a downturn in Australia.
"Trevor Janes is talented, respected and extremely honest, becoming successful as a result. He is nothing like the opportunists of the GFC."
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