https://void.cat/d/TBFrU6cfj599YNeqoNmW4c.webp
Cheat mostly. I've bought most of my queens and the source usually paints a colour coded dot, depending on the year of birth.
The swarm hive made it's own queen. They're larger than the workers with a much longer abdomen and it was harder to spot her. I got lucky with my first inspection as there aren't many workers. Come July, this will be almost impossible.