Mark those calendars, Kings of Leon fans. Bassist Jared Followill has shared a big piece of news: The band's sixth album, which is the follow up to 'Come Around Sundown,' should be out this September.

Other key details revealed by Followill? The record is indeed finished and is in the process of being sequenced. Also, it's not the grown-up affair Followill thought it was going to be.

"I thought we were going to make a really mature album but I'm amazed how youthful it sounds," Followill told NME. He placed the new material in the context of other KoL records, saying, "It's like a mix of 'Youth & Young Manhood' and 'Because of the Times.'"

The Kings of Leon released 'Come Around Sundown' in 2010, and after the album dropped, they stayed busy by getting married and having kids. They also dealt with some other issues and a little bit of band chaos, like tabling a tour after a show in which frontman Caleb Followill took the stage while appearing to be incredibly drunk.