I doubt any more items will be upgradable ever. I think STS is sorry they ever made the original mythic helm & armor upgradable as it has lead to endless threads like this with folks asking for every other item to be upgradable.
In Pocket Legends we never had a single item that was ever upgradable through expansions all the way up to level 76.
And you know what? It's more fun that way as you actually have something to do in the next expansion. The problem with having gear upgradable is that the legendary items from the new campaign are not worth very much as there is little demand for them, and so then nobody wants to farm elites because it is not worth the time for the little money that can be made, and the end result is a boring PvE part of the game.
The only interesting thing you could farm in the Shuyal expansion was the archon rings and that was because the mythic ring was not upgradable. Architect helms and armors were worth less than 50k because everyone upgraded their mythics. I don't want to see a repeat of this in the next campaign. If there is I may be bored enough that I will find a new game.
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