prOOne
In saying secondary masters, I was really referring to hardware. Wouldn't use the term wrt software. However, I have experience managing, for example, Litton 211 Omega, for which Ferranti (Edinburgh) wrote the software updates every 2 years for changes in the geomagnetic field. (On BBC Bs!). In time, Litton became agitated at their lack of foresight, and asked for the (big) total support contract back. Demanded, actually. Refused, on the grounds they had no UK facility at the time and had shown no committment to supporting our (RAF's) software configuration, which many years past had, by necessity, gone off at a tangent to the US's. The benefit of having a design custodian. But your point is well made as more and more companies are getting wise to the money they can make from UK MoD.