I find flightstats better than flightaware for tracking down this kind of thing. The Event Timeline for this flight is pretty clear what happened:

https://www.flightstats.com/v2/fligh...htId=985481398 (scroll down)

Note that the "Record Created" is just a few hours before the flight, which is atypical for a scheduled flight but normal for last minute ferry / etc. And you can see the redirect to AID and then changed to IAD one minute later that was highlighted by another poster already.

I like how they assign baggage claim belts to ferry flights. Just in case, I guess?