Comparative delays
If I remember aright, the civil Airbus range of products were all delivered to their first operator(s) within one year from first flight, with all their internal passenger care equipment functioning from day one. That's why I find the Boscombe schedule "relaxed".
One contributor finds that there's no comparison between checking out an aircraft variant and delivering a fully-functioning factory or industrial installation, but anyone involved in the whole process of getting an airliner "off the drawing board" and into service will tell you it's also an industrial process - there has to be a lot of concurrent activity, with production lines to be built and equipped, for example.
Apart from the refuelling pods, there are also quite a few excrescences on the "Voyager" which has gone to Boscombe (OK, there's also a spacecraft of that name, so should the RAF's craft not have a "III" suffix rather than the "II" I suggested?), so is it now up to people at Boscombe to do the wiring up, if the kit's so special that UK Eyes Only applies?
And, once again, how long will it take for Cobham to spool up?
TriStar replacement has been urgent for ages - so isn't the current arrangement a bit of "pie in the sky" - "You'll get this shiny new aeroplane chaps - we've got a wizard wheeze to make it look as if it's not costing anything, but it's still going to take time" ...