Summer Savings Punch question...

I'm not sure how this works.
I know that with 5 punches (5 purchases), you get +5% off New Releases, +10% off* Non-new releases, 2% off Gift Cards.
But how long is that for? Is it only valid for one day OR one purchase? Or the duration of the summer savings sale?
What happens when you get to 10 punches? Do you get a higher discount?
Comments
It is cumulative and, as far as I know, persistent.
And the discount increases by + 5/10/2 each time you add 5 punches. So that 25 punches you would get 25%/50%/10% discount respectively. As Richard says, it seems to be persistent for the duration of the sale.
TD