If I switch the display resolution for 1080P160 to 720P60 by writing to the sysfs interface, the display resolution size changes to 1280x720, but the pixel clock frequency does not change resulting in an output that is 720P120 instead of 720P60.
For example if my mode is set to the following:
cat /sys/class/graphics/fb0/mode
D:1920x1080p-60
If I change the mode by writing the following:
echo D:1280x720p-60 > /sys/class/graphics/fb0/mode
I can then see that my resolution has now changed to 1280x720, but the pixel clock is stuck at the 1080P60 speed, which results in a vertical frequency of 120 Hz.