Ba Duan Jin Qigong #1

How many different versions of the Ba Duan Jin (Eight Pieces of Silk Brocade) Qigong are there? I thought there would be one unique sequence, but today I restarted a practice with the sequence below, from the YouTube video by Judy Young at

I am going to try to compile a set of lists of what I think are different versions of the Ba Duan Jin. I remember each of these exercises, except for the last, which makes me think there are a number of different versions. Does anyone out there have any experience in this or anything to contribute? Thanks.

Preview

1. Warm up, swinging arms

2. Two hands, upholding the sky

3. Pulling the bow

4. Crane spreading its wing

5. Looking backwards

6. Left and right swing

7. Up and down stretch

8. Diagonal knock

9. Toe and heel bounce

This one is new to me. I remember the others, but not this. Hence, the question, how many variations are there?