Tax Residency does not equal visa status residency.
It could have been possible that the OP was a tax resident for
New Zealand purposes while on working holiday visa, which under normal treaty rules would automatically make her a "deemed" non-resident for Canadian tax purposes. Especially if all she had no "house or spouse" (i.e. no home that was treated as a residence, and no spouse or dependents) in Canada.
When she got her work visa in October 2009, she would DEFINITELY be a New Zealand tax resident (and factual non-resident of Canada), no question on that. (again, this assumes the no "house or spouse" in Canada).
As agnelson said, the OP should file a departure tax return for either one of the two dates mentioned. This is to ensure that she doesn't have to file a Canadian tax return again until (if) she returns, and also to make official that none of the income she earns in New Zealand is taxable in Canada.