They've repeated exclusive Trusts over a year old at least once so fa, either through events or by being able to trade a Red Pell for themr. They will repeat again. No Trust is one-time-only. Pay attention for Alter Ego Extravaganza, as that's when NPCs sell them for various currency, and also look at the login campaign item lists.

http://www.playonline.com/ff11us/cam...n/login29.html

Change the number in the last bit to see previous ones. Notice that they introduce a new one every month since December 2013? Also, in recent months they've had 3-4 Ciphers total per month. Those are the repeats.