You can use "Selection bug 2" project attached to my above post. Both articulations in it are 6 beats and I can do this three ways:
1: Right click articulation 1, select Cut (or Copy), go to the start of articulation 2, right click the articulation track, and select paste, or
2: Select articulation 1, Edit > Cut (or Copy), go to the start of articulation 2, Edit > Paste, or
3: Select articulation 1, Ctrl+X (or Ctrl+C), go to the start of articulation 2, Ctrl+V.
Now it will appear that the pasted articulation replaced the existing one, but check the event list and you'll see both. Try to resize the pasted articulation and you cannot. You have to drag the pasted articulation outside of its bounds in order to "free" it from this co-existence. When you do that, you'll see that the previous articulation is still there and was not replaced.
Drag and drop does not do this as it does not allow the dragged articulation to be moved such that it overlaps the existing articulation