You might have missed it since there was literally no mention of this in any of the recent updates, but the recalibration is back.
It looks to be staggered, so not everyone will have it available right away.
The info text also says that it'll be a yearly thing from now.
Source: https://www.reddit.com/r/DotA2/comments/t1ktq6/psa_ranked_recalibration_is_back/