I know so many people who do flagpole and are never asked about the current status nor do the CBSA ask for a study or work permit
One of my colleagues at work applied CEC and his work permit expired
He applied for visitor visa and got it for one year
His visitor visa expired when he got his medicals
He chose not to renew the visa and got COPR within the three month time frame where you can stay in canada after your status expires
He went to border, they never asked him anything and he was fine
Inland cic guys will definitely ask for op,s expired work permit and will be a problem
I think going to the border is a better option