Three "research flights" equals three delivery flights.
Zero cost
Hardly zero cost. Zero cost would be to fly it from Seattle direct to Australia. Flying down to LA then over to JFK then back across the US would add tens of thousands of dollars fuel burn alone.
Equally, flying over the Atlantic to LHR for the other flights will have a significant cost. Not to say it’s not a a
PR stunt but they are paying for the exposure, it’s certainly not zero cost.