Back in March, George Shelley revealed he had left Union J and in the weeks that followed, the rest of the band (Jaymi Hensley, Josh Cuthbert and JJ Hamblett) revealed they were on the lookout for someone new to replace him and keep the band a four piece.
The boys then revealed earlier this month, that they had picked X Factor star Casey and now they've revealed exactly why he is the best person for the job.
Union J appeared on Loose Women earlier today, to introduce Casey as their new bandmember.
He explained how him joining the panel came about and told host Ruth Langsford: "It's all new, it's all fresh. Me and Josh always used to speak before when I was in Stereo Kicks and he dropped me a message a couple of months back, asking if I would be interested in coming to meet them and their management.
"I went and here I am today, really. It's happened really fast," he admitted.
"We all had different suggestions and Casey was the one I brought to the table," Josh added. "The boys went, 'Why didn't we think of him?' And it went from there. Casey stood for us."
Revealing why he made such a good impression on them, Josh said: "He looks the part! He sounds the part and he's a lovely guy."
Jaymi then added that Casey has been through the same process as them, because he too auditioned for The X Factor and got put together in eight-piece boyband Stereo Kicks, and then released music following the show.
"It's important to us that someone knows what it takes," he said. That, and that they think they look better and sound better as a four piece.
Casey's appearance with the boys comes after he has been settling into Union J. Following the band's big reveal a few weeks back, Casey told fans he was "so happy" to be a part of Union J and was excited to get started.
The boys are currently working on their first album with Casey and are planning to head to LA to record. Jaymi teased that they will be working on a "hugely new sound" for the band, and Union J already have a tour lined up later this year in September.
They revealed that they are still on good terms with George (in fact, he had text them all before the show to wish them luck), despite the controversy surrounding his departure.
When it was revealed George had left Union J, reports claimed the band had pushed him out after he refused to commit. However, a rep for George insisted it was a "mutual decision" and that the others were "jealous" of George's new found success following his time on I'm A Celebrity.
At the time, Jaymi dismissed any rumours of "jealousy and ill-feeling", and he told fans he was "utterly heartbroken" to see George go.
Reflecting on his exit during Union J's Loose Women appearance, Jaymi admitted it had given him anxiety as he panicked about the future of the band.
He explained: "It was sheer panic. We love what we do. We're not just in it for the fame, we love music and we love our fans.You see bands just disappear overnight and I was like, 'Oh my god. I wasn't prepared for this.' What do we do? This is our career."
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