By the ﬁrst of May, your successfully wintered hives should be busting. Splits or nucs are made at this point to prevent swarming. You should be inspecting your hives every seven to ten days for swarm queen cells.
If swarm queen cells are present, it is best to remove the brood frame(s) from the hive. You should have a nuc box or new hive boxes (split) available to place the brood frames with queen cells. Do not remove the nurse/worker bees from the frames. Replace the brood frames with either comb or foundation. Place the nuc or split as far away as possible from the parent colony to prevent them from returning.
Cutting the queen cells off & not removing the brood frame does not work most of the time as swarm prevention because they are already on their path to swarm. This practice might give you a few days if you don’t have equipment ready to accept the brood frames, but it is very risky & only delays the inevitable.
The removal of brood frames with & without queen cells will decrease your population for a short period, gives the queen more space to lay, allows more room for the bees, & shocks them back into their regular routines. Strong hives with well populated brood frames & good laying patterns of more than 3 deep frames of brood in a 10 frame story & 1/2 or 5 medium frames of brood in a 10 frame triple medium should be watched more carefully for queen cells or considered for removing some brood frames. Sometimes removing only one brood frame is needed. If no queen cells are present on these brood frames, you can place them in a weaker hive.