The EU region client will be published at regional midnight (so each countries local midnight).
This thread was added on March 25, 2019, with posts from Jeff_GGG.
Original Post
https://www.reddit.com/r/pathofexile/comments/b5a6tt/ps4_game_not_in_ps_store/
Does this mean we can't download the game before servers go live?
As soon as you're able to download the client in your country you'll be able to immediately login and begin playing.