Now, this is just my own little post-pub "Tom Clancy-esque" mental exercise regarding these recent A-50 shoot downs and the spate of other "longer than usual" ranged attack on SU-34/35 etc and seen as though everyone else is having a wild guess I'll have a go too. Again, just some wild drunken theories here not to be taken seriously, unless its later found out to be true in which case "High Five!" -
The US does have a very potent Surface to Air missile with the range required and the capability to hit, not just large slow moving aircraft at long range (something considered easy), but also hit small agile fighters filled with EW too at those same longer than expected ranges (something much harder to do) and last year the US Navy/Army have both tested this firing this missile from what looks like an over sized ISO container looking box fitted on a truck. This missile can be guided into the general area by the current Patriot system in Track Whilst Scan mode so any Russians wouldn't know they're being tracked and under attack until the missile's own radar goes active about 30 seconds before impact.
Ladies and Gents I present the upto 290 mile ranged SM-6 using the Mk70 Launcher as tested in Oct '23 -
Which is just as likely as the thoughts that Ukraine is already secretly using F-16's. I do however like Rroff's idea but with a simple tweak - the IR Guided Short Ranged ASRAAM can be fitted onto the back of a flatbed truck, which Ukraine already has, and these have a 25km range, so if you can smuggle in one of these systems into Russia and, as we already know the "usual" A-50 orbit area, drive one of these under it, that'd be pretty cool.
Regarding the video above of flares being fired by the aircraft and a missile exploding early, both chaff and flares would be fired at the same time, any radar guided missile which is decoyed by the chaff would self-destruct once it loses its target after it flies through the chaff and there's no plane infront of it. There's no "5 minute chase" between a missile and a plane IRL like the film Behind Enemy Lines would have you believe!