March 22, 2021 is just the date of the most recent version of the new vehicle warranty. Going all the way back to 2012 when it was just the S, the SRS warranty has been 5 years/ 100,000 km.@mongo, as per the link from Tesla Canada that you provided,
"For further details, please review the New Vehicle Limited Warranty. This summary applies only to vehicles purchased directly from Tesla on or after the date listed on the New Vehicle Limited Warranty; any Tesla vehicles purchased prior to that date are subject to the applicable New Vehicle Limited Warranty effective as of the date of purchase of such vehicle directly from Tesla. You can find your applicable New Vehicle Limited Warranty in your Tesla Account."
The New Vehicle Limited Warranty is effective on/after March 22nd, 2021, so no, with my June 2018 purchase I am not entitled to the revised extended warranty which now includes 5 years, 100k km warranty on supplemental restraints. My Tesla Account Waranty has no such inclusion. Tesla did not have to honour the extended warranty for my vehicle, but they did, and for that I am thankful.
Going on 4 1/4 years, over 43k km and to date I have spent a total on maintenance of $76 CAD for an air cabin filter. Take that ICE!
(Also verified the 2017-2018 pre-Y version, both attached)