Instead of considering Ha1-27 as the first glyph in a solar cycle (an approximation of 365.25 - 365) we can now see a more probable meaning, viz. to be the last glyph in a sequence of glyphs:

25 349
Ha1-26 Ha1-27 Ha7-33 Ha7-34 (378)
26 glyphs  = 8⅔ days 350 glyphs = 3 * 116⅔
9 days 117 days

Its function could be twofold: to make a signal of 'here it ends' and at the same time accomplish the task of creating whole days.

Maro (feathers) were used to mark border lines:

"The name of the residence (maara noho) of the king, of Hotu, was Oromanga. The name of the place where the roof of the house had been covered by Nuku Keku was Hare Topa (sic) Tuu.

Nuku Keku was also in charge of the feather garlands (maro), which served to mark the boundaries of the royal residence. He had pounded (the staffs with the feather garlands) into the ground.

The middle (te tini) was located in front of the bay of Hanga Rua. The feather garlands went up, continued, and reached Puku Parari.

They went up again and reached Puku O Heha. From Puku O Heha they formed (a line) to the side, to Aro Huri. From Aro Huri they turned again toward the sea and reached Maunga Koua, went down, went their way, and reached Hira Moko. (He) made a second line (? he rua taupa) of feather garlands."

(Ms. E according to Barthel 2)