Yes, but weren't those RRE / Elliott prototypes using FMICW? Hence, in 1976, Marconi seemed to be the only choice for primary AI24 contractor. Ferranti (perhaps because they lost this contract?), the same year built a team and gained the experience necessary to build the Blue Vixen and CAPTOR.
What transpired with Marconi might I feel be partly blamed on the difference between designing a test radar and flying it in some benign test flights in a Canberra and operating a radar in a Tornado in day to day service, in mock combats. The Canberra is pretty nimble for a bomber, but I doubt the tests involved close combat etc.