Hi Gabriel thanks for your suggestion.
I’d like to remind you that item based benefits Like lootboxes, kit rewards or the prior stick donations are made for usage on the world that’s currently active. Saving up your keys does not give you an added benefit because all youre doing is postponing you getting items you could be using right on activation.
Essentially you’re stopping yourself from using the benefits yourself instead of using them as they come.
In short, keys are not intended to be saved up but to be used. Saving them up is personal preference.
We can not reinstate any keys from the previous world as they are meant to be used in that world only. Lootboxes often change per season/world or at random. And it would also beg the question if we should also reinstate any kits used during your time in that world. It’d cause an overflow of early good items in a new world. It’s simply just not a good idea economy wise and compared to other players.
With your Fabulous rank however which does last a lifetime you can still redeem new keys every week. I myself suggest to open them as you get them to make full use of any items you might win.
Have a good evening