I have a notification at the top saying "Austin Evans promotion redeemed! A $15 credit will be applied automatically to your next eligible drop." I'm wondering how this works, it doesn't really seem to clarify the details regarding the promotion. What is the next eligible drop, does this promotion only apply to a few select eligible drops and doesn't apply to all massdrop products? Does it apply to all massdrop products over $15? How do I find out the details regarding this promotion? What about products below $15? Any explanations would be appreciated. Thank You.