The article's research is poor, IIRC we have three T* C2 and three T* KC1 making 6 ac capable of carrying pax (K1 can carry pax, but have very limited baggage capacity), but the limiting factor is the number of ac fitted with DAS.
This is definitely worth reporting on though; the bottom line is that we cannot operate an effective airbridge and the elephant in the room is that FSTA is unlikely to be much better despite being considerably more expensive than it ought to be.
2x C2, 1XC2a, 4xKC1 and 2xK1 is the T* fleet.
as you said, a KC1 in the correct role is fine for a Herrick Pax run. The K1 is pretty pointless in that role. All of the above is in the public domain.
As you will appreciate I will not go into the ins and outs of the DAS fits of the various AC however the DAS fit is not a limiting factor.
I will however disagree with your assertion we do not maintain an effective Airbridge. I know how many AC do the Herrick run each week against how many are programmed to go against how many Pax are due including Aeromed requirements. I will admit we do not get a 100% sortie rate but the numbers we do get (which a quick Google does not find so although I was sure they were in the public domain so I won't specify them) are, in the huge, huge majority of cases effective at getting people moved as required. Do people sometimes get delayed, yes. But that happens if you book a holiday to Lanzarote as well.
216 work very very hard to maintain this, and while things do suffer (training, tanker sorties etc) the Herrick Airbridge is always number one priority.
Are the difficulties encountered worth reporting on? Most definitely. Unfortunately what is reported on is normally incorrect and the problems we face go undocumented in favour of much more headline grabbing factors, some of which exist only in either the reporters, or a misinformed Paxs mind.