Blizzard has announced that tier sets from Shadowlands Season 3 and Season 4 will be marked as Legacy with the 10.0 pre-patch, effectively disabling them.
With the initial release of the Dragonflight pre-expansion patch (version 10.0.0), class set bonuses from Eternity’s End (9.2) will be marked Legacy, effectively disabling them in combat.While it’s routine for us to mark older set bonuses as Legacy, we do not normally take this step so soon after they were acquired.