08/24/2009 AT 12:00 AM EDT
Expect big changes when new episodes of The Hills
and The City
start up again on Sept. 29, moving from Monday nights to Tuesdays. The Hills
will air at 10 p.m. (EST) followed by The City
at 10:30 p.m. (EST).Liz Gateley
, senior vice president of series development for MTV and executive producer of both shows, tells PEOPLE that the new day is the tip of the iceberg when it comes to the switch-ups.
Most notably, Kristin Cavallari
has replaced Lauren Conrad
on The Hills
. "Kristin has brought new life to the show," Gateley says. "She is the same Kristin we know and love -- not afraid to mix things up. Her presence has really changed every dynamic within the cast, especially with Audrina Patridge
and Justin Bobby
As for newlyweds Heidi Montag
and Spencer Pratt
, Gateley says they may be taking another big step in their relationship. "Heidi and Spencer are entering some interesting new territory of considering parenthood," she says.
Over on the East Coast, Whitney Port
may not be considering motherhood, but she will be dealing with a new boss.
"A lot has changed in The City
," Gateley says. "We shifted the focus of the show significantly from a relationship drama to a workplace drama. Olivia has a new job and an amazing new boss at Elle
magazine. Whitney is focused a lot more on her work now that she’s single
, and Kelly Cutrone
-- who I love -- takes on a much bigger role in the show."
But the focus on fashion remains the same. "The show feels much more like a reality Devil Wears Prada
," Gateley says. "Our whole shooting style changed. You’ll see much more action and less sitting and talking, which was an intentional choice we made in making over the show. There are fireworks on the jobs constantly -- it’s very exciting and fun to watch what it’s like to work in the world of New York fashion."Tell us: Are you more excited for the return of The Hills or The City?
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