Last I heard, it was still laid up with a tarp over it. Ask this in the LocoNotes Yahoo group -- they will find out the current status.
At one time we had a thread here with the satellite coordinates for the storage location, and it was possible to identify the tarped unit easily. You might see if you can find that post and determine what's there as of the last update of the satellite imagery.
Locomotive was given touch-up painting and some maintenance at Jenks (North Little Rock) in mid-May 2015. As far as I know it went right back into storage after that was done.
For the record: something made UP take the engine out of service a year into the Obama administration. I personally don't think the conspiracy theory about Holder's Justice Department suing for copyright infringement of Air Force One holds any particular water, but an alternative theory - that the locomotive might constitute a particular target for vandalism - may be more sensible. It will be interesting to see whether UP brings the locomotive back into service at some point in the Trump administration... it may be a long, long time before it is used to pull GWB's funeral train.