PSSE's Critical Calculation Function

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Prior to PSSE's internal function of determining the critical clearing time, we developed a python automation that checks the cct of a line. It initially checks the rotor angles of all plants at 2000ms fault duration. If unstable, it will then check at 1000ms, then 500ms, then 250ms, etc. Basically, it checks the rotor angles in fault durations between the last stable and unstable times (for example, at 1000ms it is unstable then at 500ms it is already stable, then it will 750ms next). It is quite the same with what PSSE did to its cct function. My only question is, does the PSSE internal function considers tripping the faulted line?

For context, i got a 430ms cct using PSSE's internal function with 180degree angle treshold. Then I manually tried dynamic simulation using 430ms WITH LINE TRIPPING and it showed rotor angles beyond 180 degrees. I got curious why PSSE tagged it as still stable if rotor angles went beyond the set treshold. Then i tried doing the same simulation but this time WITHOUT LINE TRIPPING and rotor angles stayed within 180 degrees.

So is it safe to say that PSSE's internal CCT function does not trip the line during the process? If yes, do you think it's correct? I think it's more appropriate that the line should be tripped to simulate actual fault clearing. What are your thoughts?