Does Pub Matchmaking reset each Season? Let’s test

My bud is attempting a different strat.  He no filled and threw about 19 games this morning.  He had a lot of fun griefing by picking out someone off drop that separated from their team, knocking them, and then letting their team kill him.  This resulted in us actually getting several "normal" feeling games (not bot lobbies, just normal mid) until we won one and ended up back with the usual try hard masters three stacks playing double scan in pubs.