I don’t know in which intervals this occurs, I mostly see it when looking at the widget on my phone or data on Apple Watch, showing knots instead of km/h wind speed. Opening the app I see it’s not logged in anymore and asks me to chose units. I have the password and email in my keychain (created with log in with apple). This happens maybe once a week but isn’t correlated to restarts of the devices or app updates. Background app refresh in enabled for windy, mobile data as well. I believe this happened with the previous version well.