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In-game Bonus Item Codes
Recently, players have noticed that the in-game bonus codes included with FFXIV-related merchandise have been character-specific rather than being account-wide. The reason is because there is a limit to the number of items that can be distributed service account wide, and it is currently difficult to increase this limit. We’ll continue looking into this moving forward, and will provide an update once we have progress.
This was posted in a Live Letter Digest from January 28 of 2018, and unfortunately we have still not received anymore word on their progress on the matter. I would recommend that someone with access to Yoshida and/or the development team bring this up with them when possible to see if any progress has been made.