Different Premium Time-Lengths

This should - hopefully - be a nice quick and easy one to answer. Recently, I stumbled upon something that allowed different lengths of Premium, depending on how many nuggets you were willing to spend. Anything from a few days to 1 year was available.
Now, no matter how much I search, I can't seem to FIND it. Can anyone point me in the right direction please?
Thanks...J

You can find these options by clicking on the rightmost tab of the union pacific shop.

Ah, thanks. Haven't visited the shop in a while. That explains it. Thanks so much.