You can't actually prove by this that support is safe. for instant, if the CAESAR II output shows failure at these SIF locations, what will be the approach? are you going to reduce the reactions by adding flexibilities? In my personal view your piping system to be designed for optimized support load with the required level of flexibility only. and support calculation shall be performed for its strength and local stresses in the parent pipe for generated loads if the support standard doesn't provide the allowable values.

also this is interesting to know the basis of these SIF value of 4.