Looking at this one I would say it was an old one, you could see the marks on the floor where it stood. I have no idea what they intend to do, just happened to spot it as I was leaving. There are two other tree masts that I could see near to this one, not sure if any of these are new or if they have always been there.
I doubt they would just remove one without reason, might be getting a brand new better one! Ill keep an eye out on my next visit.