Quinn8it

I know nothing about Box-Squats, so i am completely unqualified to comment on your form..

looking at your squats from a LBBS perspective, they look really good. Its not a great angle to judge knee travel- but they look good to me. Way better than most form check vids i see!

a couple things:
you are going well past parallel, a good bit deeper than necessary for a LBBS.
As i said, i don't know these well- so maybe thats how they should be executed.

and- this is whats a little confusing to me.
other than the bit where you go past depth- and stop, and then re-start, this is basically a LBBS performed with less weight to allow you to execute the start/stop. i assume the Start/Stop and the Past Depth are to focus training on puling yourself out of the hole on a heavy single.
To me the rest of your movement range is just a normal squat done at lower weight. since you are not training for 1Rep Max Squats, why not just do regular LBBS at lower weight?
I suspect that the part of the Box-Squat that makes it harder and require less weight be used is not really advancing your bike training.
I feel the same about Overhead Squats. yeh- i know overhead squats with 135lbs are hard- but are they focused and effective?

i would think the Box is overcomplicating things- and frankly id worry that as the weight got higher you might be in bad position with regards to back strain coming off the box.. but like i said- I'm not educated on this method.