From the T&C:
Each member is responsible for keeping up to date on Aeroplan regulations and the amount of Aeroplan Miles in his/her account. Aeroplan shall attempt to send statements, newsletters, and other correspondence and materials to members who have had a flight, car, or hotel transaction within the last statement period. Aeroplan shall have no liability for any failure to do so.
Each member shall be responsible for advising Aeroplan of any change of address. Aeroplan shall not be liable for misdirected mail, or any consequences thereof.
Aeroplan reserves the right to cancel the Aeroplan membership of any Aeroplan member who has not earned or redeemed Aeroplan Miles during the three (3) previous consecutive years (excluding any sign-up bonuses). Any member whose membership is cancelled will have all accrued Aeroplan Miles forfeited and he/she will be removed from the program.
Find the full T&C for AP at:
https://www.aeroplan.com/en/about/ab...conditions.jsp