For a system for which level C service conditions are specified in the Design Specification, ASME Section III Subsection ND requires "the conditions of eqs. ND-3653.1 (a)(9a) and ND-3653.1(b)(9b) shall be met using Service Level C coincident pressure P and moment (MA + MB), which result in the maximum calculated stress. AutoPIPE appears to use the "Peak Pressure" when performing this calculation. If the Service Level C coincident pressure P differs from the Peak Pressure (Level A and B), how can the Level C pressure be specified for this calculation?
AutoPIPE conservatively used peak pressure as it isn't able to identify the load case to get the coincident pressure from. Reprocess the results manually to check the affect of this.
ASME BPV-III-1-ND, AutoPIPE Nuclear Piping Code FAQ