The Polish national train control system is not really a ‘protection’ system like Indusi/PZB, even though the transmission technology is identical. It’s more like an additional vigilance system. On top of the normal timeout-based one (czuwak, Sifa, DSD etc.) you also have to acknowledge every signal you’re passing, using the same button or pedal. You’ve probably switched it off along with the czuwak. AFAIK, the SHP ‘magnets’ are placed a few hundred metres before most signals and/or at the location of exit signals.
Schyrsivochter's post in PZB (Indusi) Or Similar? was marked as the answer