The March 9, 2020 Banned and Restricted announcement is live! Here's the full list of cards in every format.
Golos, Tireless Pilgrim is banned
The following cards are moved from suspended to banned:
The following cards are moved from suspended to legal:
Underworld Breach is banned
Once Upon a Time is banned
We should expect a significant metagame shakeup due to these changes, as well as significant drops on Underworld Breach and Once Upon a Time. It is notable that Heliod, Sun-Crowned and Walking Ballista were mentioned by name in the section regarding Pioneer's lack of changes, but it's not yet clear if we will see these banned in the future.
The bans take effect as follows:
Tabletop Effective Date: March 10, 2020
Magic Online Effective Date: March 10, 2020
MTG Arena Effective Date: March 12, 2020
Link to the full article by Ian Duke on the mothership.