I found the answer on the CIC web; 9 |; M+ u" o3 L: R- w9 r, B8 ?"The certificate must have been issued no more than three months before you submit your application"2 T g% Y/ t; k; C2 K- N E9 ]
( t% ]" u( [5 P% L2 ?
Ours were more than one year when we applied.