I made a deal with the dogs. I’ll let you do what you have always wanted to do, flush the bird. But, in return, you can only do it when I ask you to.
I use a verbal “all right” cue. Once the dog is in the birdy area and points the bird, “All right” does not mean flush the bird. It simply means do what you think is right to stop the bird (if it’s running), manage it, and prepare it for the flush. I can’t expect the dog to do an aggressive flush until it has established where the target is. The goal is stylish, thoughtful bird management, an aggressive flush followed by an instant stop to flush.