Just having a quick look at the second set of images.

If it were aircraft codes, as seems more likely in this set; could the original have colour coded the aircraft lettering so you could distinguish between the various Squadron ‘A’ coded aircraft for example? Although some way of differentiating them without colour would be better so it could be preserved after copying 🙂

Each turning point could be represented an area (as opposed to a point) to record the aircraft passing. Slower aircraft, or possibly the more accurately flown aircraft spend more time in the area and have longer boxes at that altitude. Although differing wind speed/direction at altitudes could also affect this, if not accounted for. Or maybe the longer boxes denote a radius from the turning point. Closer you are, you get a 1 unit box, 3 miles out for example, you get a 3 grid square long box.

The early/late seems to make sense to record whether the aircraft are on time (designated by ‘M’) at the turning points , but I wonder why they don’t have just +1 etc. It could be to make entry into an early computer easier (the letters represent the variables to the computer) or onto some type of coded punch card as they did on the loss cards (along the edges).
The timing page gives a nice histogram.

But perhaps I am over thinking it 🙂

Do you have a copy of the ORS form that this seems to be the workings for?

Greg