I read this from the official Neighbours Twitter account yesterday.
They've announced that the character of Byron Stone will now be portrayed by an actor named Xavier Molyneux.
I felt sorry for the previous actor who played him. That's because Joe Klocek had joined the soap as Byron but would have likely found out the show was being cancelled soon afterwards.
There's still no word on the status of Byron's sister - Nicolette - who was played by Charlotte Chimes for a couple of years.