I wouldn't go that far with my speculation, but the Eagles are depicted in full zone 5 afterburn. Based on their configuration, they are in an ascent. That actually means they are posing for photos… But if it were an op, they would be accelerating and punching through the sound barrier to extend their missile range and improve the PK (Probability of Kill) and engagement envelope… In short - they are burning for an intercept.
However, there is another reason: "select zone 5, you can extend and escape; save your aircraft." When engaged by a missile, typically a SAM, you will vector onto a ray from the firing platform and climb. You select zone 5 when you need a lot of altitude and a lot of distance to keep the missile from reaching terminal stage.
Chaff/flare are only effective when the missile is in its terminal phase of guidance as the goal is to confuse the missile's sensors enough that it can't reliably put the shrapnel cone from its warhead into the flight path of the plane (air to air missiles are basically rocket propelled claymore mines).
On the other hand, I could just be rattling off trivia. There again… Q's way of posting stuff reminds me of a much more seasoned and planned way in which I like to post things. My ego is massive enough to allow me to question if I am fucking trolling myself via time travel. It's absurd… But I am basically left with absurd explanations all the way around for things I experience… So I just pick my favorite one to go with for the day and have fun.