The system static pressure is calculated in the non-blocking evaluation framework. The caller may set up callbacks that react to the asynchronous calculation results. If no callback is set up (e.g, called from third-party applications), the calculation is automatically switched to synchronous calculation so the caller can access the up-to-date result. Similarly, the public method get_ParameterValue(BuiltInParameter.RBS_DUCT_STATIC_PRESSURE) has the same behavior. Due to this change, the parameter RBS_DUCT_STATIC_PRESSURE no longer supports dynamic model update.