She appears to be on the phone because she has an earbud in her ear and a long very visible wire to the phone. She waves quickly and dismissively at the press and then heads up into the plane. As she climbs the steps into the plane, she puts the phone to her ear.

It's actually that last part I find especially funny. Some people questioned whether people really use wired earbuds anymore. But if they were working and you were really on the phone with someone, why would you then need to put the phone to your ear? If she's actually talking on the phone at the top of the steps, why is the phone away from her mouth? It's like she was doubling down on the "I am on the phone" message to the media, sorry I'm just too busy to take any questions. //

mopani
a few minutes ago
She's not trying to avoid the press, she's giving the press plausible deniability for why they don't hound her for answers. Don't a bunch of them fly with her on the same plane? The whole charade is for the rubes, not the press corpse.