What will be my proof of ownership for RTB? February 28, 2020 02:47 Updated You will receive your Confirmation of Sale (COS) via email within 30 days after issue date. Related articles What is a Premyo Bond? For RTB purchase, I already funded my account but the prompt still says not enough buying power. Can I order RTB anytime? Can I order RTB from overseas? Are RTBs risky?