The 65-year-old is banned from managing anyone else's money until 2019 and is also prohibited from running a company until that time.
While many white-collar criminals turn to gardening while in prison, Herbert spent his time getting cooking qualifications, his parole board decision says.
As an insurance broker, Herbert's company was paid clients' premiums and forwarded the money on to insurance companies, taking a commission from it.
The company was required to keep these customer premiums in a separate account.
However, between February 2009 and when the company went into receivership in March 2011, customer premiums were transferred into Herbert Insurance's operating account and used to meet a variety of Herbert's and the business' expenses.
The amount involved was about $2.5 million, said the Serious Fraud Office, which brought the prosecution against Herbert.