[2021] When do GGG usually reveal the next league release date?

I want to take a week off work and rush to 100 on leaguestart, something I didn't do since Delve league.

But obviously when you take a week-long vacation you need to warn the team 3-4 few weeks in advance. So I have to decide this week.

When do GGG usually reveal the release date? Can we already be sure that it starts on April 16th, or could it also be April 23rd?

I'm assuming a lot of people had the same problem many times. How do you deal with it?