I've got a few epic buldings on turtle level. How can I redo the upgrade and upgrade them to llama?
2 Answers
As far as I understand from playing the game and the few things I came across, once you have finished a an epic building, the level it reached is the only level it has.
From this thread:
You have a limited time to complete an Epic Project once you start it. When the timer runs out the project tier you reached (Turtle, Llama, or Cheetah) will determine what type of building you get.
However, there is no actual limit to the amount of epic buildings you can make (with upwards of 60 designs), so you can always make more and try to reach llama or even cheetah levels. (That thread has an entire Q&A on epic projects/buildings)
Also see the video that EA provides for tips on epic projects/buildings. (In the video they say, "make sure you at least hit turtle to complete the project").
You can demolish an epic building, replace it with a brand new plain residential building, upgrade it fully and wait for a new epic on it.