So back in 2019, comp was bugged (role queue implementation, I believe), and it looked like a MMR/SR reset from the player’s perspective.
It was chaos. No one was happy about it. Not the GMs, not the bronzes, not the Chois. Here’s a forum thread from that time period.
It was pretty obvious it was a bug after Choihyobin (SF Shock off tank, rank 1 previous season) got 2 SR after a win, but until then, it was ridiculous.