Dear Graham,
 
do my opinion and own experience  it is better to put the old queen into a
new hive at a new site. I usually take one frame with open brood cells (the
rest are frames with foundation) and put it at the place of the old hive.
This old hive will get the elder flying bees (without the old queen). I
destroy the produced Q-cells of this hive a few days later and can requeen it
or unify with an other (possibly the old) hive. The old queen will more
likely loose its swarm-tendency by this way.
 
But independent of that the old queen may have been too old. They are mostly
the elder queens that have the tendency to swarm. So hardly any of the common
methods for prevention of swarming can fail.
 
sincerely
 
Reimund
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Beekeeper in Germany (Bavaria)
Queen Rearing of Carniolan Bees
Insemination Station
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