"... It is difficult to estimate accurately the length of a month. According to the European calendar, a month (that was used by the Polynesians) has alternatively twenty-nine and thirty days; and a traditional month, based on lunar nights, has thirty days (ME:50, Barthel 1958:242-247).

Also, the time intervals are not consistent throughout. Whenever explicit mention is made of the time spent in a place, the actual dates are omitted. Toward the end of the calendar of dates, discrepancies occur: the 'one month each' (etahi marama) as the duration of the stay at Pu Pakakina, or at the yam plantation, is incompatible with the established dates for the months 'Hora Nui' and 'Tagaroa Uri'.

The total amount of time taken up by the activities at Pu Pakakina (surfing, installing the ornaments and the stone figures, trip around the island, naming places) seems to have been five days. But five days is precisely the time span that recurs directly or indirectly in alternating positions on the calendar!

It is exactly one-half year from the departure of the explorers from Hiva to their return to the homeland. Whatever method one uses to convert the six months into days (six synodical months = 177 days, six lunar months = 180, and six solar months = 182), there still appears to be an artificially constructed scheme.

Arrival and departure are accompanied by intermediate stages that amount to ten days. In all, the actions of the explorers are fixed by fourteen dates, which can be arranged into seven pairs of dates. These seven pairs, whose number corresponds to the number of explorers, are made up of 35 + 5 + 5 + 5 + 5 + (corrected) 5 + 10 = 70 days or seven groups of ten days each. Half the time [of 70 days] is taken up by the sea voyage, the other half by events on land. So far it is not known what coded information is concealed in this scheme ..."  (Barthel 2)

My explanation of the numbers follows here.