There is no real process though their FAQ has a description about sending an email requesting this. I haven't seen anyone reporting they got any response to such mails. You will have to time it properly to decide when BLS receives the document (say OCI) and visit their office before they mail it out. It also depends on their good graces, and your luck. Based on limited experience shared here, it seems BLS Vancouver and Brampton are more reliable with this than BLS Toronto.Interested to know when you pick up and what's process do you have to call / email BLS , I vaguely remember the BLS person telling me to pick it up you have to call the call centre and ask them to hold at BLS even if u had paid from 3 to 4 pm it's would be available for pick up
There is a lot of related discussion here last few days -- scan this thread.
Let the process play out if you can wait.