Entry exit points for colon to stomach channels

My understanding of this is that LI20-ST1 entry exit block is treated on the same side. This region being the only point where a channel crosses the midline of the body, provides a fundamental connection between the left and right sides of the body. The idea of entry / exit blocks relates to the movement of Qi through the channels as it follows the horary clock flow. This implies that every second day the Qi is flowing through a different side of the body, which may correlate with the idea of consecutive days alternating between Yin and Yang as per the theories within stems and branches.