ZH, you are of course correct, however I did not say they did have nose VT fuses fitted; I was describing how the original VT fuse was a nose fuse.
There was a presumption that bombs intended for impact would have had the 76 Nose and 75 Tail pistols.
There is also the possibility that the aircraft was loaded for both airburst and ground burst options. It all depends on how the bombs were preped and loaded as the fitment of the nose fuses would have been done in the bomb dump and not on the aircraft.
The 90-way bomb distribution system and the fusing and isolation switch options were at once incredibly simple and overly complicated depending upon ones training. For crews who had only trained for a nuclear mission the switch to conventional operations would have been very rapid. Dilution rates among Navs Rad was high in the late 60s and 70s so long term memory would have been fading.