2. We should arrange these 7 stars in parallel with the glyphs in the G text. The border beween the 10th and the 11th hours is just beyond Ga4-4 (because 600 / 1440 * 365¼ = 152.2):

period 7
Ga4-1 Ga4-2 (*150) Ga4-3 Ga4-4 (88)
  Ras Elaset Borealis (149.7)    

Maybe the 7th henua period is to be understood as the beginning of a new season, with 1 + 3 glyphs in positions similar to what we saw at Naos:

Ga2-21 (52) Ga2-22 Ga2-23 Ga2-24 Ga2-25 (*120)
Markab (115.7), Procyon (115.9) σ Gemini (116.7) Pollux (117.2) Azmidiske (118.4)  
Tane Rogo Mauri Mutu
Ga2-26 Ga2-27 Ga2-28 Ga2-29 (60)
χ Carinae (120.9) ω Cancri (121.4) Naos (122.3)  Heap of Fuel (123.1)
Night of prayer. Sand is returned to the beach from the sea.

From Ga2-26 to Ga4-1 there are 85 - 57 = 28 days. From Ga2-21 to Ga4-4 there are 88 - 52 = 36 days.

Beyond the 4 glyphs in the 7th period there follow 11 glyphs distributed over 5 short periods:

period 8
Ga4-5 (*153) Ga4-6 (90)
  Regulus (153.7)
period 9
Ga4-7 Ga4-8
  Adhafera, Tania Borealis (155.7)
period 10
Ga4-9 Ga4-10
Algieba (156.5), Tania Australis (157.0)  
period 11
Ga4-11 Ga4-12 (*160) Ga4-13
period 12
Ga4-14 Ga4-15

Line a4 has 9 periods with 27 glyphs and beyond period 12 there are 3 periods with 12 glyphs:

period 13
Ga4-16 (100) Ga4-17 Ga4-18 Ga4-19
      Alkes (166.6)
period 14
Ga4-20 (*168) Ga4-21 Ga4-22
Merak (167.2)    
period 15
Ga4-23 Ga4-24 Ga4-25 Ga4-26 Ga4-27 (111)

11 / 24 * 365¼ = 167.4 is just beyond the position of Merak and therefore manu kake in Ga4-21 belongs at the beginning of the 12th hour.