Studio Lerche cannot give 20 episode for this cause they do not own COTE they are only in charge of animating it and do whatever they want with it, the ones that are in charge of episode count is KADOKAWA, the producers inside, cause they are the ones giving MONEY to Studio Lerche for how much episode to animate. I'm guessing, KADOKAWA wants to just rush through 1st year arc and finish in 3 seasons and then, move onto the 2nd one so they can properly, adapt it there, cause of S1 changes they think they cannot adapt this year properly.
Studio Lerche cannot give 20 episode for this cause they do not own COTE they are only in charge of animating it and do whatever they want with it, the ones that are in charge of episode count is KADOKAWA, the producers inside, cause they are the ones giving MONEY to Studio Lerche for how much episode to animate.
I'm guessing, KADOKAWA wants to just rush through 1st year arc and finish in 3 seasons and then, move onto the 2nd one so they can properly, adapt it there, cause of S1 changes they think they cannot adapt this year properly.