What does 1 Kings 16:8 mean?

Baasha’s son Elah became king of Israel in the twenty-sixth year of Asa’s reign over Judah. Elah ruled from Tirzah, but only for two years. 1 Kings 16:8 - Modern Text Bible

(Elah, Baasha’s son, takes over as king, but his reign is short. The timeline is anchored to Asa, the king of Judah, showing the overlap between the two kingdoms.)