To be clear and Shane can correct me if I am wrong. We can buy a sander today and use the Voucher next October, Nov Dec, until 12/31/2017.
It's not money off ahead of time or at the time of purchase, there is zero reason to wait to buy that new Festool. Where I come from this is called a rebate. And it will take 3-5 weeks or whatever to get the rebate.
The voucher states it can not be used on previous purchases, but becasue of the way this works it really means it cant be used on purchases made before Nov 1st, 2016.
And if someone tries to sell you the voucher code for 10.00 you will need the serial from the tool as well or you are out of luck.