hi sidharth
well you should apply for the police check now normally they are valid for 3 months but when the cic will get that they should not be older then three months cuz according to them when they will make the final decision in one year they will take them valid its strange but it is like that , i have applied for canada in 2010 and in 2011 , in 2010 i couldt score enoguh points cuz they have not awarded me with the points of adaptibilty of my aunt i filed my application by my self it was my mistake because cic wants the notarized affidavite of the person there to prove the relationship whichi didnt provide at that time , second time my file was perfect but could reach there on time and the cap was reached so it will be the third time i will apply again if NOC 3131 will be in the CAP i am discussing with some lawyers as well this time they are insisting that 3131 will be in the cap (inshalah) now i have previous police checks of my home country i havent travel there but even then i got the fresh pcc form there and from australia as well ,
well i am not the single applicant i will apply with my family i.e my son and my husband
but you can send your police checks later after sending your application but my opinion is better to send all of your documents together
Regards