Curious as well that the newly-formed Air UK quickly ditched its jets at the same time as BMA was beginning to build up its DC9 fleet, as well as modernise its 707s to keep them in service for another four or five years. Also, 1980 was the year Dan Air finally pensioned off the Comet and began a slow acquisition of more modern jets in the form of 737s, more 727s and, a little later, the 146. Different strokes for different folks and all that.
I always enjoyed seeing the BIA and Air UK Heralds, especially when their numbers were decreasing in favour of additional F27s. I wonder if it would be fair to say that BIA got the better deal with the Air Anglia merger ? Their man got the top job and was able to immediately begin withdrawing his old bangers and later have the opportunity to reincarnate BIA and thus more or less carry on where he left off.