You bet! You can use the pre-estrus whine Sept 1st. The older cows come into estrus first, so it's not a surprise to bulls if they heard one early on, more a welcome than anything!! If you get a good response from a bull and he's heading your way throw in a spike or raggy squeal along with your cow calling, this really cranks a bull up and he seems to put it in another gear, just make sure your setup is one where he can't see you or where you're calling from exactly, you want him to have to search for you. If he seems to hang-up out of range, get whiny with the estrus sounds followed with dry huffing instead of whimpy bugles. This has worked for us a time or two!! Good Luck! ElkNut1