I’m not sure if this is a localized issue or something other people are experiencing, but here goes.
I am an Operations agent for an airline at DEN, and we use FlightAware almost exclusively to track our inbound aircraft. In the last few weeks, I’ve noticed that as the plane is approaching, and the countdown goes to 0 minutes, where it used to just say “n/a” or “arriving soon”, now it adds 10 minutes to the estimated arrival. I have a clear view of the runway from my office and can see most of our planes land, so I know the 10 minutes is never correct.
It doesn’t add the time on my phone though, only on the website.