I can't imagine there's any regularity to it beyond what I said!
If a show has those seats, if they're dropped to regular price, if they're sent to TKTS and when, would seemingly vary show to show and day to day.
Maybe qolby, it might be worth it to call the box office of the show you're interested in asking. They'd likely be the best positioned to know your answer.
Words don't deserve that kind of malarkey. They're innocent, neutral, precise, standing for this, describing that, meaning the other, so if you look after them you can build bridges across incomprehension and chaos. But when they get their corners knocked off, they're no good anymore…I don't think writers are sacred, but words are. They deserve respect. If you get the right ones in the right order, you can nudge the world a little.