What does 1 Kings 12:32 mean?

He created his own festival, like the one in Judah, but held it on the fifteenth day of the eighth month. He offered sacrifices on the altar he built in Bethel, and he made the people of Israel do the same. 1 Kings 12:32 - Modern Text Bible

(Jeroboam invents a new holiday to replace the one in Jerusalem, further separating his people from their old faith.)