"No, [it was] not difficult, really," Lewis told Digital Spy. "I've been with Sony for eight years. They've given me my launch pad and now it's time for me to make my own tracks in my own way.
"For me, it's like leaving home. It's like, 'Bye, mom and dad. It's time to go out and live my own life'. I'm really being able to spread my wings, fly and make something for myself now."
Speaking about her choice of new label, she added: "I went with Island because I like their creativeness and their individuality.
"The artists they have are really allowed and enticed to express themselves freely. What more can you ask for a label? It's amazing."