Herbison, who has worked on the soap in various positions since the '90s, has landed the post of series producer at the long-running drama.
Digital Spy can reveal that Neighbours' executive producer Richard Jasek is leaving the show.
Despite the different title, Herbison is Jasek's successor as he takes over the day-to-day running of Neighbours. FremantleMedia's head of drama Jo Porter now serves as executive producer, while Laurence Wilson is associate producer.
Fletcher, who plays Karl Kennedy, told Digital Spy of Herbison's appointment: "It's a natural fit. Richard Jasek has been one of the finest executive producers the show has ever had, and he's actually moving on now. He leaves the show in an excellent state after a year of increasing ratings in the UK and Australia.
"I go back a long way with Jason, and Jason goes back a long way with Neighbours. He's written for the programme over the years, and as a journalist he's also written about the programme.
"One thing that is a real hallmark of Jason's work is that he is a massive fan of Neighbours and always has been. He has an encyclopaedic knowledge of the show - he knows it backwards! He's such a fantastic producer and writer for Neighbours, because his passion for it is so strong. He's got some great ideas."
As 2014 marks 20 years since Fletcher joined Neighbours with on-screen wife Jackie Woodburne (Susan), many fans are hoping for a big Kennedy storyline to mark the occasion.
Discussing the possibility, Fletcher commented: "It would be lovely. The main wish of course is that the Kennedy children all come back to the show for some reason or some event.
"The 20th anniversary celebration isn't necessarily something you would write into the script because it isn't intrinsically a Neighbours story, but it's almost without a doubt that Jackie and I will be having a celebration."
Herbison gave his first interview as Neighbours producer last week and has also announced plans to bring in Scott and Charlene's son Daniel Robinson.
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