I'm starting to remember if I overloaded my computer after exiting Heroes, after lunch?

It doesn't change anything.

Maybe I'm just glitching myself?

It happens sometimes :)

After returning from lunch and loading Heroes again (naturally, a new session), this PPB didn't want to repeat, but a new PPB started to form with similar actions!

Here, you need to check everything from start to finish: army arrangement, the cell from which you attack the enemy hero, etc. That is, the initial conditions must be the same. In addition, in your case, the first battle must be won for the PPB to form. Maybe you played the first battle incorrectly the second time (for example, you fled or paid them off)? Or, as an option, the first time you recorded not a PPB, but a random battle.

However, after your save with the double PPB, I'm already starting to doubt...