Hi again!
I received my ADR (Additional documentation request) to provide a "Certificate of Conduct" for the Netherlands (aka
Verklaring Omtrent het Gedrag, VOG) yesterday after medical clearance, on the same day. I have 60 days to get it and upload the document.
I recommend to follow the IRCC instructions. Some applicants sometimes try to find a walkaround or are too impatient and don't follow the instructions. I know some cases where IRCC still asked for an addtional police certificate later on because the candidate did not follow the procedure. To be honest, I'm sure IRCC appreciate when applicants follow the rules and do what is said. You want IRCC on your side and PCC problems is a sensitive topic and quite common cause rejection. You never know how strict the visa offer may be. Plus they give you time to get them.
It's all clearly stated on their website how to proceed for Netherlands police certificate or for any other country.
http://www.cic.gc.ca/english/information/security/police-cert/europe/netherlands.asp
So if, like me, you receive your ADR to provide a Dutch police certificate, here is all the official info in
English 
on how to request a Dutch PCC, from the "Justis" website:
https://www.justis.nl/producten/vog...ere-can-I-apply-when-I-am-not-registered.aspx
They even explain how to fill in the form.
Cheers,