They are saying you can book UP TO 180 days out. I would wait awhile before booking because payment is required immediately and is NONREFUNDABLE. I would also book it early in your trip, because if it is raining the morning you want to do the driving, they cancel for the day, and you will only get a raincheck for a later day. If you wait until late in your trip, you may not be able to get the driving in before you leave.
The drive can be transferred to any Richard Petty Experience in the country.
Carol