I've always understood it to be as indicated in BOAC's link, i.e. What indication will my altimeter give on landing at ... (place) at ... hours, my sub-scale being set to 1013.2 millibars (29.92 inches)? or On landing at ... (place) at ... hours, with your sub-scale being set to 1013.2 millibars (29.92 inches), your altimeter will indicate ... (figures and units).
But as CJ suggests, I suspect too suspect that QNE has become commonly used to represent SPS - I have heard it used in that way a good number of times.