The applicable exam principle is the presumptive three-year limitation or “three-year rule” for retroactive child-support adjustments. Counting back three years from November 2018 produces November 2015, making option B correct.

The Supreme Court of Canada's framework in D.B.S. v. S.R.G. established that effective notice is highly important in deciding the commencement date for retroactive child support and that, as a general rule, an award should not extend more than three years into the past. The Court described effective notice broadly: formal court proceedings are not required; the support issue merely needs to have been raised with the other parent.

Later Supreme Court authority continues to recognize the three-year presumptive rule, while emphasizing that it is not absolute. Factors such as blameworthy conduct, failure to disclose income, the child's circumstances, delay, and hardship can justify a different result.

For FPII examination purposes, with November 2018 as the relevant notice date and no additional facts establishing exceptional conduct, the three-year look-back identifies November 2015.

FPII reference/topic: Family Law — child support; retroactive support; effective notice; three-year presumptive rule.

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