PR working with temporary SIN

[Bloodrose]

I soft landed in 2018 and was recently offered a job in Ontario to start next month. When I soft landed I only stayed for a few days and didn't have a fixed local address for a PR card and SIN so I couldn't register for either at the airport. I did return to Canada for a trip last year and applied for my PR card whilst I was there but they're dragging their heels over that application. Unfortunately because I landed over a year ago, I cannot apply for a SIN with Service Canada using my COPR as proof of status.

I still have a temp SIN from when I was on a TWP and when I checked last year it was still valid. My question is could I provide that SIN to my new employer using my COPR and (if required) also my R-1 as proof of status and start working and then update my employment records once I have a permanent SIN?

The official documentation suggests that using a 9-prefix SIN also requires the employer to check you have legal status.

https://www.canada.ca/en/employment-social-development/programs/ei/ei-list/ei-employers-sin.html

Ensure that all employees who have a SIN beginning with a "9" are authorized to work in Canada and that their immigration document has not expired.
SINs beginning with a "9" are issued to temporary workers who are neither Canadian citizens nor permanent residents. These temporary SINs are valid until the expiry date indicated on the immigration document authorizing them to work in Canada.

• Ask to see the employee's existing immigration document authorizing him or her to work in Canada (e.g. work permit, study permit) and verify that it has not expired. If the immigration document has expired, ask the employee to contact Immigration, Refugees and Citizenship Canada (IRCC) to obtain a valid document and to provide it to Service Canada to have the new expiry date entered into their SIN record. Take the necessary steps to renew or rehire the employee.
• For more information about hiring or extending the work of temporary foreign workers, visit IRCC’s Hire foreign workers page or contact the IRCC Call Centre at 1-888-242-2100.
• For more information about hiring a foreign student, visit IRCC’s Hire international students page.