Brown top millet

I was thinking about planting some brown top Millet for grazing In the next 5 days. I would burn down clean with Roundup and plant. The field is in wheat and it is currently being grazed buy Dairy heifers the wheat is about shot and there's some natural grass is in there that I know will leave as soon as it gets a little hotter. I'm wondering if anyone has any experience grazing Brown top millet and I was also wondering what rate you planted it at and how quickly it's Grows,. I'm kind of planning on planting it letting the cattle in it in 3 weeks if it rains and then in mid September notill triticale and oats into it without tilling or spraying

Brown top millet