Could you elaborate on that? What would constitute NOT having to certify to the newest revision of 13485?
When you certify to a standards, you are probably under a certification scheme (if not, your are probably being scammed

). The rules of the certification scheme define the requirements. If the rules says that the certification is for the 2003 version, even if the 206 is already out, you will be certified to the 2003 version, not the new one.
I just mentioned this in a general way, because a lot of people thinks that because ISO 13485:2016 is out, there's an automatic need to certify to the new standard. ISO TC 210 WG 1 even published a suggested transition period, but this document is only a suggestion to the certification schemes (although it;s usually followed) - meaning, the certification schemes have to define the need to change to the new standard.