PDOS is the mandatory seminar that needs to be attended in either Manila or CEBU. You receive a sticker for your Passport which allows you to exit the country with your Canadian PR document and Passport.
We booked our flights on Jan 17, as I am already flying back to Canada on that date, and wanted my fiance to fly back on the same day. If we end up moving the flights to a later date, not a big deal. We also bought cancellation insurance just to be sure. A gamble lol, but one worth taking based on the great price we got on the additional flight.