I agree to make stands around the 20 minute mark and that's only for those late comers. now calling bobcats make stands longer as it tends to take them longer to respond. in calling bobcats we've had coyotes take an hour to come in but chalk that up to they just happened to be passing through and heard the call. I'm not afraid to change calls on the stand i was calling with a guy and we could see coyotes but couldn't get them to respond so he switched calls between a few distress and it was finally a howl that brought them in. have fun and good luck in the field