I knew that part, because when the Montreal controller stops talking and his mic gets stuck sometimes, he starts talking on the hotline while coordinating. A lot of aircrafts here in northern Ontario that are handing off to Winnipeg's airspace on frq 134.07 I believe, are asked to contact the center about 15 minutes later. However, I hear aircrafts handing off to say Wawa, Ranger Lake, Sault Ste Marie who are asked to contact the center, and if no joy, try every 2, 4 minutes or every 5 miles due to range from the antenna. But, sometimes the hand off is immediate and always works. I'm sure the controllers ARE handing off at the same spot each time.