Just an idea ofcourse but perhaps, to help keep the older players happier should any more main-city attunments happen in the future, you guys can add an NPC that will allow higher rating characters to attune to every place that requires attunement under these Tier revamps (That didn't require attuning beforehand, that is). By all rights, the high level characters would have already of been attuned to Brist/Sslanis/Chiconis/Dalimond had this revamp happened when they were leveling that tier.
For example: The attunings in this delta were for the Tier II revamp, and to re-direct new players to Kion. However players ~40+ could perhaps have an NPC to go to in, say, Tazoon so they can attune to these places without the run around to do so. (Which, honestly, is all it's going to be for higher level players. More running around for stuff they shouldn't have to run around for, again because this would have been done back when their characters were tier II assuming they could have done it.)
Some food for thought, in any case. :3