Setup:
form php (onBeforeStore) setting error message + return false;
Then the form is showing the error message but all dates are redisplayed with one hour added.
Date elements are set to local (my timezone offset is UTC+1, so it seems it adding the timezone although dates are local).
Putting the identical validation in an element php validation is ok (so there's a workaround) but not nice, because it's marking this element but the validation depends on multiple elements.
form php (onBeforeStore) setting error message + return false;
Then the form is showing the error message but all dates are redisplayed with one hour added.
Date elements are set to local (my timezone offset is UTC+1, so it seems it adding the timezone although dates are local).
Putting the identical validation in an element php validation is ok (so there's a workaround) but not nice, because it's marking this element but the validation depends on multiple elements.