Feral bees found in the bush

The bees that were found living in the car park shrubs are building up in number. They have got well established in the new brood box and only have a few more frame left to draw out. I looked for the queen today but didn't see her. I have treated them with thymol crystals and the newer frames of brood do seem to have less chalk brood than the earlier ones. The swarm from North Walsham also suffers very badly with chalk brood. If I do find the queen I will remove her. I think she should be called GW. Chalk brood Treatment? Bee disorders Chalk brood treatment -- Askotat