Because the SMS blocking apps cannot make complex rules? ;-)
What I need is blocking(and as tasker cannot block yet just turn down
the notification volume) SMS notifications coming from a specific
number/name but only when there is no calendar entry in one of my
calendars(could also be when my on-duty tasker profile is not
active..because that looks in the same calendar)
I do use an app called Easy filter right now. I cannot look in a
calendar - so it is not automated