FatEric is right , the procedure is dumb!
My company [and as far as I know ALL companies in this half of the world] changes the altimiters AT transition! [that is why it is called "transition" ] This means that here in oz we both change from QNH to STD/1013.2 @ 10000' on climb and from 1013.2/STD to QNH @ FL110 on descent [in the states we change @18000' on climb and FL180 on descent] - in Europe we change on descent to QNH when told ["desc to 7000' on QNH 1008" etc]
Why make it more complicated?