Continuing…
In 1985, the Space Shuttle program was already about a decade and a half old, the shuttles themselves were already starting to show themselves as “old tech.” It was clear that they would need replacing with a next generation of vehicle, and of course Rockwell wanted to build whatever “Shuttle II” came along… if for no other reason, a Shuttle II would make the Shuttle instantly obsolete and wipe out Rockwell’s Shuttle-based income. It was obvious that such a system would enter service sometime after the year 2000. Not, of course, very long after 2000. That would be nuts.
Interestingly, the illustration Rockwell used for the Next Generation Shuttle was not a Rockwell design, but a NASA-Langley concept for a small “Orbit-on-Demand” vehicle. If you’d like more information on this exact design, boy, have I got a deal for you: it was described and illustrated in US Launch Vehicles Projects #03.