Hi,
Yes. I was in the same boat a month ago and I contacted CIC and verified with them everything.
Once you are issued the degree completion letter, you should stop working until you apply for the PGWP because they would check if you have worked after receiving the letter and before applying for the PGWP. Many people got refused because of this trick as your status changes to "Unregistered to any course".
However, you were legal working before receiving your degree completion letter.
In my case, I finished my course on the 19th of August and got my degree Completion letter on Monday the 4th of September.
I kept working from 19th of August to the 4th of September, then stopped from the 4th of September to the 7th of September where I applied for my PGWP, then resumed work on the 9th.
I also mentioned that in my letter of explanation just to be more secure.