Possibly not. The rule requires one continuous year of qualifying employment within the three years immediately before the petition. If she has completed a full continuous year since returning, or completed one before the leave that still falls within the three-year window, the requirement is met.
Count backwards three years and find an unbroken twelve months
Hypothetical example: the general manager of a Haldimand County feed mill left the payroll for fourteen months to finish an agribusiness degree, returned eighteen months ago, and is now proposed for the U.S. transfer. The test is not total years of service; it is whether one continuous year of employment with the qualifying organization falls inside the three years preceding the filing date.
Her eighteen months since returning satisfies that on its own, provided the payroll records show uninterrupted employment. Had she returned only nine months ago, the file would need to reach back to the year before the leave and confirm it still sits within the three-year window. Unpaid leave is not employment, so those fourteen months contribute nothing.
The safest presentation is a month-by-month table from payroll data with the qualifying year highlighted, plus a letter confirming her duties in that year were managerial, since the year abroad must also be in a managerial, executive or specialized-knowledge capacity.