But couldn't it be that this specific behavior triggered a spam warning? I have no insight into Reddit regarding security, but would expect new/fresh and empty

But couldn't it be that this specific behavior triggered a spam warning? I have no insight into Reddit regarding security, but would expect new/fresh and empty accounts under special scrutiny and when an account like that hops from IP to IP this would - if I were to build a heuristic at least trigger an alarm/ban/temporary lock of voting/posting functions. Just an idea regarding your latest test. The part of the main account sucks - I am with you on that.