They won't take your snakes for just the cage, they usually give you three months to fix any problem they have. They will only confiscate your snakes if you apply for the the snakes you mention and have snakes that are not on permit or not on the application, like applying for five corns and when they pitch up you have twenty. Make Sense?
As long as your setups are good enough for the snakes they won't have a problem. I doubt you are keeping a three meter Burm in a twenty six litre tub.