I've just looked at my 24, 28, and 35mm AI lenses, and all three have white 2.8 and 5.6 aperture markings, f/8 is pink and I assume corresponds to the pink lines on the scale. They also all mark f/4 with green lines, then f/11, 16, 22 with yellow, blue, mauve respectively.
Wonder if the change to the innermost marked aperture as f/5.6 was made with the update from AI to AIS?
Incidentally, the 35mm has such a compressed scale that it is fairly useless for judging DOF accurately. The 24mm and 28mm are much longer-scale.
Ian