Brilliant I understand, thanks.
So with my strong colony I fed with fondant over winter and they increased at a significant rate meaning they are very strong at the moment with two supers on (last weekend; one approx 60-70% uncapped honey, other 70% drawn comb) that even if I do swarm control with snelgrove I should be planning to go brood and half or double after or before snelgrove?
Will going brood and half or double minimise swarming? I assume so but not stop it?
They have been building brace comb up from varroa floor between frames in a couple of places so assume they are running out of space, but that was 2/3 weeks ago just before I put first super on.
Couldn't do a proper inspection last week so don't know if any queen cells.
On hot nights last year I had a lot sitting just outside entrance but last night they were bursting with a huge bulge full length of entrance and around, although it was quite warm and still air.
Cheers