Hi everyone,
I ended up filing my taxes yesterday because I was tired of waiting. While there was no indication my refund would change when filling out the form in turbo tax, after I filed I got a message from the CRA when they issued the express notice of assessment saying they reduced my 2024 income by the amount of the lump sum and taxed it as if I got it in previous years. It did end up benefitting me as my refund was higher than I expected by several hundred dollars. So the t1198 form worked and the CRA did receive and assess it, so I hope that helps everyone! I was using turbo tax online version. I saw some comments that people had to restart their returns because they started them when the form glitch was ongoing and even though the form was fixed it didn't work because they had started the return before the fix, but that wasn't my experience.
