Simon joined Cheryl, Mel B and Louis Walsh to wrap up the final audition stages at Wembley in London yesterday (31 July).
After a long day, Simon took to Twitter to give fans his usual update, and it seems like Cheryl - who shocked fans last month by announcing she married JB on 7 July after just three months of dating - certainly has the newlywed glow.
"Cheryl is the happiest I have ever seen her," said Simon. "Her new husband is a great guy."
It's not the first time Simon has spoken about Cheryl and JB. A week after Cheryl's news, Simon publicly congratulated her via Twitter, saying he had "no idea" that she had tied the knot.
Simon said at the time: "I still can't believe my lil buddy Cheryl got married. Had no idea. He is a great guy. Am very happy for them."
Last night, music mogul Simon also had praise for former Spice Girl Mel, who has joined the panel for the first time this year.
"Mel B is a total star," he tweeted. "She flew in from New York last night. No sleep. And totally on it. She is a revelation."
And it seems like the talent has left Simon impressed: "Last day of X Factor auditions today before we start the arena shows tomorrow. Two amazing auditions. Both 17. A boy and a girl."
The eleventh series of The X Factor will hit screens later this year, and with Simon and Cheryl on the panel, it'll mark their first return to the show since leaving in 2011.
Last week, X Factor announcer Peter Dickson revealed that he'd been busy practising Cheryl's new name ahead of the live shows.
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