I found the answer on the CIC web;4 o6 A2 b/ X8 Q: I) P8 @# V1 n
"The certificate must have been issued no more than three months before you submit your application"1 i+ K9 `7 x% }+ u- X1 A/ \* ~7 o
" ^8 o& |. }3 O- ?+ }
Ours were more than one year when we applied.