What Position?
Problem is that there is more than one "Position" at an airfield.
As a matter of fact, as has been pointed out on another thread, "position" can be anywhere you are, or are going - as in "Hold position" -ie stop where you are. Then of course, we have the "Holding Position". Quite a salad of opportunites for misunderstandings there.
"Line up" or "Line up and wait" while on the ground, can only really mean on the R/W.
And by the way it was changed to "Line up and Wait" from "Line up and Hold" a few years back to avoid even more confusion.