Boost Sales Plugin question

currently using the boost sales plugin and using the upsell feature to try to upsell and express service options that allows customers buying a product get faster service. I currently have this option listed as an upsell and it pops up on every product i have selected. Is it possible to have it only offer this options at checkout 1 time instead of when each product is added to the cart? Trying not to frustrate my customers with having to close the window on each product and only offer it one time at checkout.