Gonsac Circle

What is the Gonsac Circle? How does the Gonsac Circle work? What are the different Gonsac Circle tiers? Do my previous orders on Gonsac count? How can I check my progress? If an order takes me through several tiers, will I receive all the intermediate Loyalty Credits? Does my progress reset to zero when I use Loyalty Credit? How do I use my Loyalty Credit? How long is my Loyalty Credit valid? Can my Loyalty Credit be combined with other offers? What happens in the event of a return or refund?