This is what I call the 2nd period:

The person in the 2nd position is now sitting down, and will be so through the rest of the periods. I also think this person is a she, because of the pouting stomach - which I believe is a sign of pregnancy.

The sitting position perhaps has something to do with 'seating' of a period to come. But which period, the month, part of the month (Waxing Moon?) or the '2nd period'?

Logic tells me that it should be the '2nd period'. Otherwise why repeat this sitting person so many times, once for each of the seven periods. The 1st period perhaps does not need a 'seating' because there is a major 'seating' for the whole month in the 8th period of the preceding month.

The six moon-like signs at the right I believe to show six taboo-free nights. That might explain why the 4th glyph from the left is showing such signs of vitality when all the seven corresponding glyphs in the other periods are 'tired old birds'. Freedom it shouts!

The 5th glyph ought to show a sun, a fish and a sign from the sun towards the moon, probably indicating a stream of light. But I cannot se any sign of a fish. And the sun is shown only by its central disc and one flame upwards, which looks as a diamond. From this fact and other indications in other texts I think this diamond might be a sign for the moon.