A bit more info from page 9 of the manual...
http://www.cic.gc.ca/english/resources/manuals/ip/ip04-eng.pdfEligibility for permanent residence
Live-in caregivers may apply for permanent residence after they have worked full-time for at least
24 months or a total of 3,900 hours within the four years immediately following their entry into
Canada under the LCP. The total of 3,900 hours of full-time employment may be completed in a
minimum of 22 months and may include a maximum of 390 hours of overtime. As part of their
application for permanent residence, live-in caregivers are required to select one of these two
options (24 months or 3,900 hours) for determining whether they meet the LCP employment
requirement.
Live-in caregivers must meet the requirements of the class as specified in R113 at the time of
their application for permanent residence. The live-in requirement is an important element of the
LCP, as there is no shortage of Canadians or permanent residents willing to work as caregivers
on a live-out basis.