Hello All,
Thought I'd update you all since many of you were kind enough to make useful suggestions.
Today was a lot less problematic. We went about 1pm, the weather was overcast with a slight blustery wind.
We did as suggested and took it very slow removing the roof and crown board and gently smoked the top super.
The colony is on brood and a half, with 4 honey supers, and we had to separate and remove everything down to the queen excluder. The bottom two supers were crammed with bees (maybe 'cos we'd smoked them down) and so heavy I wondered if the side bars would support the weight of the supper. The second top super they are starting to drawn and store honey, the top super is largely just foundation. We have reordered so that the two heavy supers are above a clearing board and we will remove tomorrow.
Considering that this was quite a process, removing and reassembling the hive and exposing the queen excluder, there was far less defensive activity, there was of course some bees on our veils, and some bees did persist to buzzing us some distance from the hive, but not anywhere close to the extent of a week ago, which was just horrible.
What did we do differently...
Different time of day.
Cooler weather
Different smoker fuel - wood chip which gave off a far thicker smoke.
We went with extra gloves, and second layers under the suits and were far more confident because of it.
We were very pleasantly surprised when they didn't erupt from the hive as soon as we cracked the crown board as they had last week, and that helped enormously.
They are still more defensive than our other colonies, one of which just ignored us as we removed capped frames and brushed the bees off back into the super, but they were not as problematic as we feared.
Thanks again for your suggestions,