I've been desperately trying to figure out the following task, but I'm not able to find a solution:

I want to create a shifted copy of an extruded spline feature that has a coincident mate on point (1) to point (2):

The result is supposed to look like this:

But I'm not able to create a linear pattern that moves the feature correctly from point (1) to point (2). I created the above image by entering a fixed distance for the pattern, but that's not what I want.

Mirroring would copy the spline to the correct position, but it would also mirror the spline's direction, which is not what I want, too:

Can someone please help me and give me a hint on what I need to do to get a linear copy of the spline that's based on point (1) to point (2), so that when point (2) is being moved, the copied spline will move along?

Is there perhaps a Mirror option that's shifting the copy but not rotating it?

Your help is quite appreciated.

Please find my current Part file in the attachment.