CRA will not accommodate a late filing under s. 216.1
Where a non-resident actor provides acting services in Canada through a related corporation, for instance, a U.S.-resident actor providing such services through an LLC or S corp, the 23% withholding tax under s. 212(5.1) on the gross consideration paid can be avoided if the corporation files a Part I return for the year by its filing due date therefor and elects therein to have s. 216.1 apply. CRA considers that if the non-resident corporation misses this deadline, there is no ability to access s. 216.1, and (based on s. 115(2.1)) the non-resident corporation cannot late-file a “regular” Part I return where the provision of the acting services had resulted in it having a Canadian permanent establishment under the Treaty.
Neal Armstrong. Summaries of 27 July 2016 T.I. 2015-0603271E5 under s. 216.1(1) and Treaties - Art. 16.