I would actually prefer 1080p@24Hz over 2160p@60Hz. 4K (2160p) is beyond human visual acuity at regular viewing distances, and 60Hz requires 3:2 pullup on the video signal that I find distracting at times.

Likely HDMI 1.4, 24fps @ 4k, 30fps @ UHD. Interestingly the new Apple TVs hardware is capable of 4k even though it does not currently "support it" (HDMI 1.4, and A8 with can play 4k)

Where does it say HDMI1? The only versioned thing I see in reference to the video stream is HDCP 2.2.