Presented here are some pages from the Walt Disney Productions Annual reports from 1974 and 1975.
You can see in these pages that The Rescuers (1977) was in production
and both The Fox and the Hound (1981) and The Black Cauldron (1985) was in early preparation.
As for The Black Cauldron's script development, Rosemary Ann Sisson is mentioned to have written the film's script. (It makes me wonder, how does her early script compare to Lloyd Alexander's rejected script and the final finished film?)
and what is also interesting is that The Black Cauldron had a different title: The Cauldron.
1974 Walt Disney Productions Annual