-1.
You can call to confirm they will work in advance and get a $0+tax total.
Basically, there's a number on the coupon to call for reservations, you give them all the info, plus the coupon codes and number of coupons being used. You can also call the regular listed reservation line, or preferred, presidents, etc.
If it's not valid for those dates (blackout, etc) then the reservation total will not include the coupons.
When you bring in the coupons is when the actual discount is applied. There generally should not be any issues for using them..