Sorry, I meant accepted_pn from the start of the function — previous_pn now.

So for the less trivial case...okay, makes sense, I guess we do want a separate value. Urgh.

Still worried about us not writing accepted_pn to disk though. Looks like we only actually write it during handle_collect(), and I'd expect that to cause a lot more breakage than the above case where we get a leader who doesn't get a commit through. Though I suppose it means anybody restarting would have been out of quorum, and if they all restart the person with the higher last_committed wins, but still.