The quantity based discount is for all products within the order, not just within a single gallery. For example, if a customer orders one gallery with 3 products and another with 7, and the discount threshold is set to 10 products, the customer would receive the product.
The second discount is a time based discount and is intended to be an incentive for your client to access the galleries quickly and purchase quickly.
These discounts are applied during the checkout process for online orders, not for in-person sales.