Hi again Steve,
I found a previous post with a similar issue.
Mark posted a reply on that topic that might help.
Using his method you’d create two groups in your hierarchy and change their positions to the start and end positions you’d like the timeline to transition from/to.
You’d then add the groups you’ve created to the relativeTo property of your node, but don’t drag your node into either of them.
Next, set up a timeline which transitions the node’s relativeToProp ratio from one group to the other.
(The ‘Multiple relativeTo values’ section of this docs page may help.)
By changing the positions of those groups through code you’ll also be changing the position that your node will transition from/to in the timeline.
Hope this helps.