The UDP-203 is available for pre-order today (in US) with a release date of December 12 for $549. The Oppo site indicates a UDP-205 will be available in early 2017.
Is anyone considering the UDP-203? I'm tempted as it has all the important bases covered with HDR, 4:4:4, Dolby Vision support coming in early 2017, etc. However it does not have built-in Netflix, Amazon, etc. Oppo states they're going for a 'purist approach to disc and file playback'. It is possible to connect via HDMI 2.0 a 4k-capable streaming device to the UDP-203 but the Oppo player does not support HDR via the HDMI in that a connected streaming device would utilize.