Copy Location "offset" not working..?

I’m running into an issue with the Copy Location constraint and wondering if anyone can shed any light on it.

Basically I have two objects, and I want one to copy the location of the other, but while keeping an offset with respect to its original keyframes.

So I add the Copy Location constraint, and click “Offset”, but the constrained object stays snapped to the other objects location.

Is it not the intended function of the Offset button to keep the original world-space position? Or is it just to allow you to move the object after Copy Location has been applied?

Its going to be location, not keyFrames

Offset
When enabled, this control allows the owner to be translated (using its current transform properties), relative to its target’s position.
https://docs.blender.org/manual/en/2.79/rigging/constraints/transform/copy_location.html
See the second video on this page, sorry if this isn’t more help - your description is really general.

Ok, I just tried it again and now it’s working. No idea why it wasn’t working originally, thanks for your help. Weird.