Hey there, TA Meta here. Good work making it through the 250 box challenge, it's a bit of slog, so let's get into your critique.

The first thing that I noticed when I looked at your submission was a distinct lack of check lines on the majority of your boxes. These check lines are there for your benefit, to see where your estimation of perspective is straying as well as for mine, as it makes it far easier to critique a submission that has them and see the problems that you're having with your boxes and help you to correct them.

That said, you've made a fair amount of progress with your line confidence and your boxes do start off strongly and some of the ones near the end are pretty strong in terms of convergences, though some of your boxes that are mushed together (I'm guessing this is an attempt at subdivided boxes, without the subdivision) are definitely seeing quite a bit of divergence going on. It's clear from some of your boxes that you've developed somewhat of an understanding of how your lines relate to one another, however it's quite inconsistent and I believe you could have strengthened this understanding by consistently applying your check lines. This diagram illustrates the concept of how the angles of your lines relate to one another as they converge towards the vanishing point.