Understanding skills generated using serial communication with the key K

The file example.py under OpenCat/serialMaster/example.py has the following skill

vt = [

21, 0, 0, 1,

57, 43, 60, 47, -18, 7, -17, 7,

50, 43, 53, 47, -5, 7, -5, 7,

43, 43, 47, 47, 7, 7, 7, 7,

43, 43, 47, 47, 7, 7, 7, 7,

43, 43, 47, 47, 7, 7, 7, 7,

43, 47, 47, 50, 7, 0, 7, 0,

43, 54, 47, 58, 7, -13, 7, -13,

43, 60, 47, 65, 7, -25, 7, -25,

43, 66, 47, 71, 7, -35, 7, -35,

43, 63, 47, 67, 7, -30, 7, -29,

43, 57, 47, 60, 7, -18, 7, -17,

43, 50, 47, 53, 7, -5, 7, -5,

43, 43, 47, 47, 7, 7, 7, 7,

43, 43, 47, 47, 7, 7, 7, 7,

43, 43, 47, 47, 7, 7, 7, 7,

43, 43, 47, 47, 7, 7, 7, 7,

47, 43, 50, 47, 0, 7, 0, 7,

54, 43, 58, 47, -13, 7, -13, 7,

60, 43, 65, 47, -25, 7, -25, 7,

66, 43, 71, 47, -35, 7, -35, 7,

63, 43, 67, 47, -30, 7, -29, 7,

]

which is executed later with the command "K"

testSchedule = [["K", vt, 2]] (See line 374 of the example.py file).

I understand the 21 is the number of frames, then the next two zeros are pitch and roll, and the angle ratio.

My question is: what are the 8 values of each frame specifying exactly? I am asking because I use it on Bittle, and Bittle has 9 servos - (hip + elbow) * 4 + neck -. Doesn't that mean that 9 values are needed? Moreover, I was trying to manually change values to understand what angle each value controls, but I couldn't really figure it out. I'd appreciate if someone can chime in and provide a little more detail.

I also read that the index are organized from small to larger, but it's the same issue, aren't 9 numbers needed instead of 8?