I am on the 2nd week of my Tuta Mail testing. So for so good. Nothing to complain about the e-mail part of it; it is fast and works as expected; about the Calendar, I got a position from the developers that they will roll back a change that made it unusable for me (Agenda view showing only one day , just as the Day view).
If you want to try it too and get a a free month when you subscribe, would you please use this link: https://app.tuta.com/signup?ref=OWZCcml5eVc.