I'd write a very, very short one unless they indicate they aren't interested. Emory, for example, says something like "please spare us your LSAT addenda" (paraphrasing) on their application.
... and was left with a poor impression of the school compared ... all. Maybe it was a poor selection on the given day ... inequity between rich (students) and poor (most everyone else in the ...
As a side note, I don't think that "not caring for ten years" makes a very compelling addendum- people usually write addenda for things like severe medical issues, taking care of a family member, etc.
I am on the same exact boat as you. I personally plan to take the September Lsat and see how I feel after, I’m just now finding out you can cancel the score if you feel as if it would be a poor representation of your potential.
171/2.93 cGPA and about to start my second week at Northwestern. You absolutely have a chance. Make sure you write a strong PS and addenda to help bolster your application, and apply to as many schools as you possibly can!
I had to submit a transcript from a school that I withdrew from in the first semester (after the add/drop deadline). I got 0 credits from that school lol. That's what addenda are for!