as the dog is starting to learn that it is good to carry the article back to the handler you can introduce the dog to sitting infront of the handler when returning with the article.
(i know i made no sense then but its getting late and im not concentrating on how to word things sorry)

#3 "Give" the easiest of all commands (your dogs would probably know this one anyway but if they dont)

just offer them a tasty treat in place of the article and they should "Give" it up.

well good luck on trialing in Open and hope to see you asking for Utility advice soon oh and remember HAVE FUN and act happy when training for ALL exercises.