I think the following would help:

https://hexagonppm.fluidtopics.net/reader/O04dxcwMfibZIK1cyksZvQ/o5VGS13yq6~~DDo8p2E6RQ

Selecting Restrained when the pipe element is not restrained means Caesar II uses restrained stress equations regardless the state of the pipeline element.

By the other hand, in case "CAESAR II Determines" is in place, it is not possible to understand what is in your Caesar model without more information available.