From
the promotion page:
Terms and Conditions
Promotion period 1st July - 31st October 2016
The Senator status discount code CDP 501032 must be quoted when enroling into Hertz Gold Plus Rewards or be put into your existing profile.
After your upgrading your status will remain for 12 months. Afterwards you will get the status relating to your rentals with Hertz.
You can also put your Miles & More member number in your Gold profile to never miss your miles. Please show your Miles & More still at time of pick up.
Hertz obtains the right to remove or change this offer at any time without prior notice.
Hertz terms and conditions of the respective country apply as well as the special offer conditions.