Chronicles II 31:7

7 In the third month the heaps began to be piled, and in the seventh month they were finished.

Chronicles II 31:7 Meaning and Commentary

2 Chronicles 31:7

In the third month they began to lay the foundation of the
heaps.
&c.] The month Sivan, as the Targum, in which month was the feast of Pentecost, called the feast of the harvest, ( Exodus 23:16 ) , for then barley harvest was ended, and wheat harvest began, and the firstfruits were brought:

and finished them in the seventh month;
the month Tisri, as the Targum, in which was the feast of tabernacles, sometimes called the feast of ingathering, of the fruits of the earth, the wine, oil and so a proper time for bringing the tithes of all.

Chronicles II 31:7 In-Context

5 And as he gave the command, Israel brought abundantly first-fruits of corn, and wine, and oil, and honey, and every fruit of the field: and the children of Israel and Juda brought tithes of everything abundantly.
6 And they that dwelt in the cities of Juda themselves also brought tithes of calves and sheep, and tithes of goats, and consecrated them to the Lord their God, and they brought them and laid them in heaps.
7 In the third month the heaps began to be piled, and in the seventh month they were finished.
8 And Ezekias and the princes came and saw the heaps, and blessed the Lord, and his people Israel.
9 Then Ezekias enquired of the priests and the Levites concerning the heaps.

The Brenton translation of the Septuagint is in the public domain.