While the company seems to be run by lawyers, if you operate on the edge all the time, mistakes will happen, but life goes on. I agree probationary pilots should always be more careful, but you don’t have to go to extremes.
I would venture to say most people on reserve Jumpseat in. If something crops up, call CRS. If you get a letter, it’s advisory, and THEN be more cautious over the next year. This job is much easier than this thread is making it out to be.
And regardless of what some may say about prohibitions jumpseating in, there are NONE in the CBA. The CBA language simply refers to protections if you follow certain rules. Without meeting the “protection” timings doesn’t mean you can’t or shouldn’t do it. Just be honest and early with your phone call to CRS, then perhaps the DO if needed. Once you get a letter for the inevitable problem that will crop up in a career, deal with it then. Many people at the 15 plus year point have received a letter or two in their careers. They go away at a year and it takes more than one to even pop onto the discipline radar.