CoPR is not required for transferring a eligible (ie: US/UK/etc...) driving license. When you get your DR it's a piece of paper while you wait for the mail, about 2 weeks normally (based on the previous 3 I've had sent).
You can request it as soon as you want, I had to go 3 times because they wouldn't accept my proof of address or employment at first (AirBnb = bad, print out with signature vs real ink = bad); it doesn't really matter if you request it day 1 or day 60, it will come shortly before day 90 and it's valid from the 91st day after you land. I wouldn't request it much later than day 90 because it takes a while to arrive and they may (or may not) give you an interim paper copy if you request it day 89. I've venture not.
They mail it out, takes about 4 weeks they said (I got mine in the post pretty much bang on 4 weeks and one day before it was valid
).
When I updated my OHIP from permit to PR I got a piecep of paper to use with my old card indicating there was something on the system to disable it hence the paper.