The latest live letter suggested 6.1 is now April.

Currently housing on Materia wa slated to be unlocked then, with the long time please consider enabling housing on Materia in the existing areas before then.

Ishgard can be unlocked with 6.1, with other regions, but access to LB, Mist, Goblet, and Shirogane will help FCs, roleplayers, and decorators all of whom are currently without any housing.