The point of my post, and my calculator, is to word it in a valid way, that's why my calculator says it that way.
You'll find further down you can do a longer term estimate by guessing at the diff change, but certainly not years

Network difficulty, changing every 2 weeks, makes a 1 month prediction unreliable, let alone a 1year prediction.

However, saying the chances in finding it in 1 day is useful and correct