Delaying the Expiry Date of Entering Canada Entry Post PR

I have one question related to Post PR. I got my PR(Express Entry from the USA) and the last date to Enter Canada is 14th November 2019 (As my Medical Examination Certificate date was 14th November 2018)r on the Documents that I received. Is there any way we are further delay the last date if we are not able to make it by that date? Can we send another Medical Certificate? Any suggestions would be appreciated.

As far as I understand, my COPR clearly says that the one time entry immigrant visa you get to enter for landing has an expiry date and it cannot be extended under any circumstances. If you have a health concern you are perhaps allowed to move the date but do not take my word on it since I do not know of any case myself.