you need a valid TRV to re-enter Canada
Hi
Kindly view this link I just found and give an interpretation please
https://www.mcgill.ca/internationalstudents/work/post-graduation-work-permit
They mentioned like below
How to Apply for the Post-Graduation Work Permit
You can apply for a post graduation work permit, Online OR At a Port of Entry (Terrestrial/Land Border* or Airport)
*Canada/US terrestrial border (Lacolle/Champlain, St. Armand/Phillipsburg, or Stanstead)
Applying At a Port of Entry:
To be eligible to apply at the border, you must be
TRV-exempt*
*Even if you were required to have a TRV/Entry Visa to enter Canada, you are TRV-exempt if you are traveling only to the US and back with a valid Study Permit or Work Permit - see IRPA Section 190 (3) (f)).
Please note, however, that not all agents are familiar with this exception and may require you to apply online once you're in Canada. This is why we recommend that foreign nationals who require a TRV because of their nationality apply only at the US/Canada Land Border - Lacolle/Champlain . All other nationalities that do not require a TRV can apply at any Port of Entry.
Please bring the following documents:
1. Valid
Passport (The PGWP can not be granted past the validity of your passport. If your PGWP was granted for a shorted period of time than you were eligible for - because your passport was expiring - you will need to apply for a new work permit and pay the fees again, once you have obtained your new passport. You should include a letter of explanation stating that your PGWP expire prematurely because of the expiry date of your previous passport)
2. Valid
Study Permit
3.
Letter from Minerva or Service Point confirming that you have completed all the requirements of your program of study
4.
Official Transcripts in a sealed envelope showing final grades/results
(border officials occasionally request these).
4. $155 + new $100 fee (as of Feb. 21, 2015) =
$255 (
payable by cash, credit card or Canadian debit)
Optional documents: Immigration officers occasionally ask students whether they have enough money to pay for their living costs while looking for work. It is recommended to have a copy of your
latest bank statement or any other document proving that you have sufficient funds to pay your rent while looking for work (there is no specific amount required by Immigration Canada)