G'day Darren,
I was about to say that less than 20% of my stocks have needed swarm control so far but I then thought, hold on, you have been managing them all season with a view to reducing the inclination to swarm.....
Four stocks began to make queen cells which prompted reactive swarm management, a couple were proactively demareed as they were very strong (14x12BB plus Std National BB plus four supers) and some couple are being used for queen rearing and are being disturbed so often they seem to be put off swarming!!
What I have noticed in many of my stocks (and in those belonging to a few other beekeepers I help out) is that over the past few weeks, many colonies have trimmed back areas of comb in preparation for making queen cells. These "hollows" are really obvious when they first appear and at the next inspection there is usually a play cup or two in or above the hollows. What I have also seen is that colonies have started Queen cells and torn them down again. I also had a cell started colony tear down 16 nice queen cells (I discovered this when I went to put on the queen cell protectors...). This activity has coincided with a change in the weather and the onset of the June gap. Since I started beekeeping in 2010, my bees haven't suffered from any obvious June gap so this is a new experience for me and it is interesting to see how the various colonies react to changes in their environment.
The colonies you mention do seem to be a little slow to build up but I have a few comparable stocks which have really just filled out their first super but are going to be spot on for any nectar flow we get in June/July. They are just later developers.