Repeated ?cast swarms on the same post

[Amari]

A few days ago SteveG of this forum and I removed a swarm (average cast size) from the leg of a bench in the chidrens' play area of our village playing field. It was given to someone a few miles away.
Next day we had another call and Steve removed a smaller cluster from the same post and then sprayed with air-freshener.
Today I was called for a cluster of about 100 bees on the same leg. This time I sprayed with insecticide because of parishioners' concerns.
I assume these are repeat cast swarms coming to the same site. Is this a common phenomenon or is there another explanation?

 

[Ian123]

Yes it’s common it’s pheromones from the previous swarms.

 

[enrico]

Mqny hives swarm to the same site. Once you know the site for each hive it makes life easy, unless it is fifty foot up a tree! It also helps you to know which of your hives may have swarmed
E

 

[Amari]

Mqny hives swarm to the same site. Once you know the site for each hive it makes life easy, unless it is fifty foot up a tree! It also helps you to know which of your hives may have swarmed
E

Thanks Enrico, but Steve and I vehemently deny the casts came from either of our hives.....

 

[enrico]

There must be other hives, maybe wild, nearby then!