RE: cant quite figure it out yet
Stepping off the yardage is a good idea. You might want to try setting your farthest decoy at the end your shooting range, so if the birds are inside the decoys you are good to go. Another idea is maybe go to a tighter choke for the longer shots. One more thing the divers fly pretty fast so lead the birds more than you think you need. Most people shoot behind their targets rather than to far in front. Hope this helps. BTW what choke and size of shot are you using.