Once you submit your application at BLS check the status at
Application Status Tracking (blsindia-canada.com)
On BLS website choose the submission type as postal and application type -passport and provide passport details to get the application status.
Once BLS tracking shows processing at consulate, track the rest of the status at
Passport Seva at Indian Embassies and Consulates (passportindia.gov.in)
On passport seva for tracking provide the reference number which BLS provided to you and the date of birth of a parent to track the status. You will see the status like initiation of police verification, Police submit clear report and PCC print on passport seva website.
Once tracking shows pcc print, call or write an email to the consulate where your application went for them to dispatch the PCC to you.
Then go back to BLS tracking again to see your PCC received by BLS from consulate and then from BLS to your home.
After submitting my PCC application at BLS, next day it went to consulate and in two days I got an email on the email address which I provided on the application form that police verification has been initiated. I got two emails one for father and the other for mother.
Provide your relative Indian phone number on the application so that police can contact them to verify your parents details.
Once I got the police verification initiated email, the same day my relative went to the police and provided my parents voter card and adhaar card photo copy and did the rest of the formalities.
I got photos of my parents at Staples 51 mm X 51 mm. I told them to print this size only.
I was asked about the letter from immigration to show that my parents PR application is in process as consulate doesn't provide PCC to visitors/tourists but I didn't take any evidence in regards to it.
You can take your SA letter. In India it is understood that wife is a dependent of the husband and hence if you are providing SA letter that has your father's name then it will cover your mother as well. Again I was asked about it but I didn't submit it and my application was accepted at BLS. I asked you to take it in case you are asked about it and you can submit the application in one visit at BLS.
Remember you need to prepare two separate applications one for your father and another for mother. Get two sets of photocopies of all the required documents.