Maturity is different in beans than in corn. Corn requires a certain amount of heat units- period.
Beans get ripe, more or less, by the changes in day length. Full season in my neighborhood is 1.8-2.6. Anywhere in there works. The last time I did some short season, such as you would be doing, I was told to use a 2.0-2.2. I was told the short season planted late would be VERY short and hence hard to combine.
Making sure soil potash levels are good is also helpful in bean production.
No-tilling behind the combine is your best option. Beans can be grown in solid stand or rows- in my neighborhood we see everything from 7 to 36 in rows.