2. Considering why there always are 3 vertical 'beams' in hau tea - it must have a meaning - and based on the assumption that it is sun beams which are illustrated, the natural conclusion will be that the three 'beams' indicate the division of the day:

"The Hawaiian day was divided in three general parts, like that of the early Greeks and Latins, - morning, noon, and afternoon - Kakahi-aka, breaking the shadows, scil. of night; Awakea, for Ao-akea, the plain full day; and Auina-la, the decline of the day.

The lapse of the night, however, was noted by five stations, if I may say so, and four intervals of time, viz.: (1.) Kihi, at 6 P.M., or about sunset; (2.) Pili, between sunset and midnight; (3) Kau, indicating midnight; (4.) Pilipuka, between midnight and surise, or about 3 A.M.; (5.) Kihipuka, corresponding to sunrise, or about 6 A.M. ..." (Fornander)

Time consisted of night + day = 4 + 3 = 7. The Polynesians considered the origin was in the darkest of night, with light arriving only later:

Fornander is not clear as to how the night was structured in Hawaii, but 4 intervals of time there were. I have put midnight in a special (black) box because it marks the 'death' of the old day (and the birth of a new day). The division ('cut') of time at midnight makes it natural to have a balance with 2 intervals before and 2 intervals after. There is no similar 'cut' at noon. Time begins anew (with a new cycle) at the darkest place. Pilipuka is the first 'season' of the day and Pili the 7th.