I recently received word from Canvas L2 support that this programming error will officially not be addressed, saying that "they [the engineers] have decided to shelve the issue at this time because the gradebook's late policy and multiple quiz attempts are not currently compatible". It's interesting that Canvas uses the exact description of the programming error that they made as their reason for not fixing it.

So to summarize, Canvas was first made aware of this programming error in February 2018. According to this thread, it took them many months to even acknowledge that it was an error and not just a new feature idea. Now, after more than 2 and half years, and despite assurances that a fix was right around the corner, their final verdict is that they won't be fixing it. In other words, Canvas is content to sit by and do nothing while their program continues to incorrectly score thousands of quizzes across the country.

When our university signed on to Canvas, I was enthusiastic due to its many features and excited about how this would benefit my students. Having a lot of features isn't helpful, though, when many of them don't function properly and no effort is made to fix them. Unfortunately, this programming error with the late penalty is only one of many examples of bugs and design flaws that seriously compromise the functionality of the program and which Canvas declines to take any action to fix. I am honestly starting to think that our university made a big mistake in adopting Canvas, and I can only hope we make a better decision the next time around.