981 B
Then it happened
This phrase is used here to mark the beginning of a new part of the story. If your language has a way for doing this, you could consider using it here.
in the twelfth month ... on the first of the month
This is the twelfth and final month of the Hebrew calendar. The first day is near the end of February. (See: rc://en/ta/man/translate/translate-hebrewmonths and rc://en/ta/man/translate/translate-ordinal)
of the twelfth year
This refers to the twelfth year of the reign of King Jehoiachin. AT: "of the twelfth year of the exile of King Jehoiachin" (See: rc://en/ta/man/translate/translate-ordinal and rc://en/ta/man/translate/figs-explicit)
the word of Yahweh came
This is an idiom that is used to introduce something that God told his prophets or his people. See how you translated this in Ezekiel 3:16. AT: "Yahweh spoke this message" or "Yahweh spoke these words" (See: rc://en/ta/man/translate/figs-idiom)