Wow! Your procedure was the reverse of things we do. Usually we teach them food call first. Then we teach them how to trap followed by surroundings familiarity. Finally we release them.
If they are responding to food call, then you are finish with that step. Trap training follows. They should trap by themselves after food call. Are they ready to come out? Well, they already did! Your goal right now is to teach them how to trap. Depending on what trap you have you either have to teach them by shoving them inside the trap or just put them on the trap and call them in. Depending on how smart the birds are, 3 minimum training sessions should be followed. If you have the bob trap, then put some settling cage to prevent them from escaping, put the bird inside the trap, then call them in. If they don't go inside either you have to catch them and shove them in. You can release the birds once they trap themselves when you give food call.