PS4 Pre-order Physical Codes get email out early Monday morning SE has just announced. This will give those users the code to put in on the PSN to allow them access on the 19th at 2am to download the game client and access Heavensward as long as all requirements are met to gain access to Ishgard.
PS3 Codes were still in testing phase and will go out after PS4 Codes have been handled successfully.
PC players I believe have already got their codes and are good to go to download client once available.
Good luck to all of us getting on at 2am...oh boy....please let me get on....LOL.