Project Runway is making big changes this season, but some of the designers aren't "too happy" about it.

ET's Denny Directo caught up with Heidi Klum at her other gig, America's Got Talent, in Los Angeles on Tuesday, where she opened up about having designers dress models of all sizes on season 16 of the Lifetime show.

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"They kind of went like this, 'Ah?'" Klum shared. "A lot of them actually weren't too happy about it."

"But this is the real world. Not everyone is, you know, runway figure or what the runway figure used to be. You have to dress real people, and real people come in different sizes: short, tall, more voluptuous, skinny," she explained. "There is many of us, and so a real designer needs to know how to do that. So get with it."

Sixteen seasons in, Project Runway is still delivering the drama, with one contestant seen walking off the runway in a new promo. 

"I mean, you have to watch and see this. I have never had this happen before, especially when I'm like, 'Hey, guys, what's going on?' and they don't listen to me either, they just walk away," Klum said. "I'm like, 'Wait a minute!'"

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"I'm like, 'What is going on here? You guys are a little too comfortable in my studio,'" she added.

Project Runway airs Thursdays on Lifetime and America's Got Talent airs Tuesdays on NBC.

Watch a promo for the upcoming season of Project Runway in the video below.