I have a little patch thats being tested this afternoon which will hopefully then be made available on the usual sites. It backdates Soton 1988 to 1981 by modifying a few buildings, vehicles and textures and disabling the Foker 27 AI aircraft for the benefit of those who prefer the Herald/Viscount/Twotter/Freighter era.
Looks like nows your chance. If someone can dig up some relevant BAF/Air UK/BMA/BA/KLM timetables, I guess someone could put together period AI for this version.
I have an early 90s version in the works too, though I guess that might be of less interest to most on here