I believe you can plant it in the spring, let it go to seed, and mow or disc it in and the seed will give you a second crop.
This is what I did last year. Planted in May and used it as throw and mow mulch in September for my fall mix. My second crop did not come in nearly as thick as the first, so keep that in mind if you want it for a fall attractant. My guess is a lot of my seed was resting in the bellies of the turkey. I only have about an acre to plant. The turkey did keep coming to it though into the Fall until first frost. My deer hit it hard too. I love buckwheat!