Ah, I saw the reply here: https://turbotax.community.intuit.ca/community/filing/discussion/net-capital-loss-carrybacks-not-see..., which is your post as well.
For future readers of this question, Moderator TurboTaxGinette said "Your T1A Request for Loss Carryback will be included with your return and the Canada Revenue Agency(CRA) will reassess your past according to your request from there."
Thanks
