While only the Bank of Canada nowadays can issue notes, banks in Canada used to have that right. Those notes can still be redeemed. The Bank’s own “pay to the bearer on demand” notes are still legal tender. There doesn’t seem to be any cut-off date, after which they’re no longer redeemable. See the Bank of Canada Act:
Similarly for coins, issued by the Royal Mint - there’s no cut-off date, and the coins issued by the various Canadian provinces prior to Confederation are still legal tender under the Currency Act:
As I read them, the dates listed in these provisions are the final dates for issuing such notes or coins, after which the Bank of Canada notes and Canadian coins are the sole tender being issued. But if a note or coin was issued and was legal tender prior to these dates, they’re still good money.