YES! You can still work if no decision is made post January 5th, 2025! Here's the direct link from IRCC.WP-EXT for PGWP letter says:
"Please attach this letter to your present Study permit Number as proof that you are authorized to work for any employer, in any occupation with no restrictions on hours until 05th Jan 2025 or until a decision is made on your application, whichever is first."
So as per this , I should stop working after 05th Jan 2025 if no decision has been made before that.
I am not sure how come everyone keeps telling that one can still work, inspite the IRCC letter doesn't say this.
https://ircc.canada.ca/english/helpcentre/answer.asp?qnum=1181&top=15