The ranks in Rocket League have changed slightly after going F2P:
Changes aren't only happening at the top. We're working to soft reset the rest of the ranks to account for incoming players picking up Rocket League for the first time. This means Ranks will shift closer to the median Rank (close to Gold III). For instance, when current Bronze players complete their placement matches, they may be placed in a higher rank since they'll be better than new players who are just starting out.
I'm curious to know how the new Rocket League ranks match up to the old ranks? The article linked above doesn't specifically talk about how the ranks match up past to present.