Dominic Treadwell-Collins has taken over the post of executive producer at the BBC show after the departure of previous boss Lorraine Newman.
With a number of characters now due to leave Walford in the coming months, McGarty was initially worried that her alter ego Whitney Dean could also be written out.
She told Inside Soap: "I was petrified they were going to get rid of me! Dominic asked me why I looked so worried, and I asked him if he was going to get rid of me.
"He said, 'No, don't be stupid!' and I was like, 'Thank God!' He told me about some really good stories they have coming up for Whitney.
"He talked to all the cast at a big meeting the other day and made us feel so hopeful about the future. We're going to be back on top, winning awards, I can guarantee that!"
McGarty also praised the decision to bring in Shirley Carter's family - including film actor Danny Dyer as her brother Mick.
She said: "I can't wait to work with Danny Dyer. I have an inkling that Whitney will have some scenes with the Carters. I've been chatting with Danny on Twitter, and he's such a legend."
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