Yes, everyone goes unranked. However, if you're someone like WildTurtle who's in challenger, once he finishes his game 0/10 or 10/0 he'll always be placed in a high rank (at least plat) because they can't afford him shitting on all the bronze players because he trolled his promos. That aside, you don't know when rito decides they wan a new season. I believe the new SR is coming out with s5