versions of HDMI and DisplayPort of Polaris cards

Greetings!
1. What are the fully supported versions of HDMI and DisplayPort on Polaris (Radeon RX 460 - 480 and 500 series) cards? If there is only partial support for a specific version of any of the connections (or a full support of a version with some features added), please make it clear.
2. If they support HDMI 2.0b (as some vendors state) why isn't it mentioned in official specifications?
I did some searching and the best official informations I found was that Polaris cards support HDMI 2.0 (no mention of HDMI 2.0b).