... Judging from the final glyphs in each of the periods it is evident that the first 5 periods constitute a group (with 2 subgroups):

1 4
Ab4-15 Ab4-20 Ab4-29 Ab4-32
2 5
Ab4-21 Ab4-23 Ab4-33 Ab4-42
3 The number of glyphs in the first 3 periods is 14, likewise the number of glyphs in periods 4-5.
Ab4-24 Ab4-28

The 3 last periods constitute another group. The first group has 28 glyphs and the second 20:

6 5 7 10
Ab4-43 Ab4-47 Ab4-48 Ab4-57
The number of glyphs in period 7 is equal to the sum of the glyphs in periods 6 and 8, altogether 20. 8 5
Ab4-58 Ab4-62

Manu kake in Ab4-43 is drawn slightly assymmetric. The left wing tip is not closed, the right wing is narrow and somewhat uplifted. The neck of the double bird is at right drawn with a broken line. These signs should indicate that midsummer lies in front, I guess.

My guess finds support in hau tea at Ab4-49, because I believe its double 'eyes' function like a sign of Janus:

7
Ab4-48 Ab4-49 Ab4-50 Ab4-51 Ab4-52
Ab4-53 Ab4-54 Ab4-55 Ab4-56 Ab4-57

Furthermore, the 10 'feathers' in haś reasonably indicates that sun has reached an end. Haati at Ab4-50 probably means a season is leaving. Mauga (Ab4-55) means 'last', maybe 'of the first part of the year' or possibly 'of the sun' - notice how the two forward flames in the hetuu glyphs are drawn 'broken'.

Counting we find that 4 * 48 (at Ab4-48) equals 192. The unusual glyph is like a vertical Janus, maybe alluding to sun 'toppling', as for instance at Te Pei in G:

Gb1-6 Gb1-7

The rightmost line in Ab4-57 (and in Ab4-62) is shorter than in the earlier group, a sign which could mean that sun no longer will reach so high:

Ab4-20 Ab4-28 Ab4-42 Ab4-57

We can see that also the henua signs are shorter. 4 * 57 (in Ab4-57) = 228 = 8 * 28½ ...