Good to read that progress is being made.
Intro to an article on Aviation Week:-
The demonstrator core of Reaction Engines’ air-breathing Sabre rocket propulsion system has successfully passed a preliminary design review held in collaboration with the UK Space Agency and European Space Agency.
The assessment clears the way for a follow-on critical design review and the subsequent development and test of the core at a newly built facility in Westcott, England, in 2020. The complete engine, which will ultimately build on the core to incorporate a pre-cooler, rocket engine and ramjet, is designed to provide air-breathing thrust from the runway to Mach 5 and beyond for hypersonic aircraft and, in rocket mode, low-cost access to space.