Since when could you go down a full rank?

I may have just missed it on a community update, but I got my team slayer to diamond 1. Played a game and lost. I’m back down to platinum 6.
I mean I kinda like it, but it’s just never been the way. So curious if I missed somethibg

It was mentioned in the previous season. Alot of players missed this important fact somehow xD

it doesn’t really matter though, the difference between platinum 6 and diamond 1 is the same difference between platinum 2 and platinum 3