Crude protein over 24% is very difficult to achieve unless you're cutting that alfalfa a week or more before you see the very first bud.

At that level of maturity, you're going to take a huge yield hit.

Here in Nevada, we cut just barely pre-bud and you can see the crude protein range anywhere from 19 to 24% for the same stage of plant maturity - 22" high off the ground, no more than 50% of the plants in the bud stage. That's the point where you maximize your yield for supreme-grade hay (CP > 22%, ADF < 27.0, TDN > 55.9). We are foliar feeding the alfalfa by injecting acidic fertilizers into the irrigation water through the pivot, and applying dry fertilizer at the start of stand establishment. To get CP's over 23%, you need perfect growing conditions, esp. for the spring cutting.

If the guy wants a CP > 24... he'd better be paying up for it, because consistently cutting your stands that early will result in a stand that lasts only four, maybe five years.