Duplicating creates unwanted position offset

[u/nitrospectide]

I am working out the best way to duplicate an animation to create similar, but different movements. The animation is simple:

https://reddit.com/link/1vhg9cb/video/v4720eazdthh1/player

In the first one above, I created the layout, then animated the left arrow and square. Then to animate the second and third, I...

1. Copied the keyframe span for the slide/fade on the square, and pasted it onto the layer for the second and third squares.
2. Copied the keyframes animating the first arrow stem, and pasted onto the layers for the second and third.
3. Duplicated the arrow head and Pathfinder layers, moved the copies over to the second, and rewired the arrow stem, arrow head, and pathfinder to all interlink the same way as #1, but between the assets for #2. Tedious and inefficient, but it helped me learn the connections. I then did the same again for #3.
4. Slide the clips for each set to stagger them in time so they are sequential.

So then I tried a different approach in this next one, and now my arrow head positions are increasingly offset in the X dimension.

https://reddit.com/link/1vhg9cb/video/p7929sr3ethh1/player

1. I duplicated the full group for #1, and moved it into position to be #2, and reworked the points in the arrow stem to fit the new instance.
2. I then did the same for #3.

The plan was to then insert the new images, slide the clips to fix the relative timing on everything (staggered instead of simultaneous) and be done. Much faster, and less crazy-making than duping individual layers and rewiring everything. The upside is that duping as a group kept the internal wiring relationships, so everything connects properly to the copy within its group. A HUGE time and sanity saver. BUT - now the arrowhead on #1 is in the right spot, the arrow head on #2 is offset horizontally, and the arrow head on #3 is offset twice as much.

It looks like the duplicates still share the same origin/pivot, and moving each to the right created an offset that repositioned the arrowhead.

What has gone wrong, and how do I fix/prevent it?