The answer lies in Canadian Aviation Regulations [CARS] 401.05, recency requirements.
The time limit after which a person would have to write the PSTAR exam again and do a flight review to flight test standards with a QFI is 5 years.
So at less than 5 years he needs to:
Have a current Canadian medical, Class 3 or better for a PPL.
Complete a recurrent training programme or a flight review.
Do 5 take offs and landings if he wants to carry a passenger.
Simplest way to meet the recurrent training programme is to complete the most recent self-paced study programme produced annually in the Transport Canada Aviation Safety Newsletter and retain a copy as evidence of having done so.
Hope this helps.
Rhys
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