@ pr00ne and others - I apologise for the substantial lack of clarity in my post No 2 which led to misinterpretation. My point, so badly expressed, was that at least on this occasion we weren't going to try and build a UK replacement for the R1s, and were going to buy from the US instead.
Subsequent reading here and in other places now suggests this may not be such a good deal after all, but as flyingblind said, what are the options? Soldier on with 2 R1s? Accept RJ as a "better than nothing" solution? Spend £Bns on a completely new system?
Or perhaps accept that these days poor old UK Mil plc simply can't afford to sustain all these capabilities any more, and forget the entire thing?