That corn should be dry enough to keep fine in the closed bin. Be careful tho if you like ear corn, fresh from the field will _not_ keep in a closed bin, it would need air curculation like a crib would offer.
With the ear corn so dry, it will want to shell off the cob pretty easily, as you dump into your wagons, and again as you dump into the bin, you will end up with a lot of shell corn on the bottom, and a lot of 1/2 full cobs on top. Might want to plan your griniding to balance that you, so you get the shelled stuff mixed with the cobby stuff as you grind.
I often found my ground feed started going off a bit after 2 weeks. A month might work and esp in winter when it's cold up here should be fine, but I'd watch that, after 2 weeks keep an eye on things.