One more piece of this part of the great puzzle. Pondering what is depicted at right in Aa1-26 I find Aa7-3 which looks similar:

In Aa7-3 we have tapa mea reversed and we can count to 8 instead of the usual (for the day calender in Tahua) 6.

The right part of Aa1-26 certainly is a variant of GD32, reasonable indeed as we are at noon. In Aa7-3 the middle part is (like a pun) the left part of GD25. And the right part of this pun is somewhat similar to the arm in Aa1-24:

Is the elbow not equivalent to summer solstice (noon)? From that we have haga (GD36) connected with the 'belly of the sun'. Then the part from elbow up inclusive hand should mean the first half of the day.