Do you think it's safe to assume that pretty much all future volumes will contained 9 episodes? I thought we had a chance to go back to 10 per volume with the series becoming monthly but it seems they kept the 9 episodes formula.
It could always change. But I think if it were going to change, it'd have happened in Vol 38, because Ep 343 has been out since December. They had every chance to include it in 38.
There was a long, bountiful time of Berserk when there were 11 eps per volume, and we got 2 volumes per year

Of course, Miura was also 15-20 years younger then.