Assetto Corsa 4K 30FPS

Recorded with Shadow Play and re-encoded using Handbake to test quality. For some reason YouTube keeps knocking down the video quality from 4K 60FPS to 1080P 60FPS If anyone knows why please let me know. This is a test in 4K 30FPS to see if I can upload properly with this setting. 4K 30FPS seems to work so Which would you all prefer? 1080P 60FPS, 1440P 60FPS or 2160P 30FPS?