Email them and explain your situation. They are really awesome to deal with, excellent customer service. I had to send my esc in right after I bought it after diagnosing the internal BEC wasn't functioning, They sent me a little envelope with prepaid postage and already addressed n ready to go. Popped the esc in and tossed it in the mailbox. But that was a factory defect, not sure what your situation is, if it's something you did to it, it may have different circumstances, I'd be 100% honest with them and see what they want to do. I know when I toast my esc or 6900, I'll be paying because it's about a year into it and/or I know I am misusing/abusing it and it's not their fault in any way. They've been nothing but really nice and professional.

BTW, that was without proof of purchase, but then as mentioned above about the MMMs, I don't think the 6900s were out for more than a year at the time I bought it.