'Below Deck's Kate Chastain on Rhylee Gerber’s Return and Her Upcoming Walk-Off (Exclusive)

'Below Deck's chief stew, Kate Chastain, dishes on the drama still to come on season seven of the Bravo hit. Plus, an ET sneak peek!

Don't mess with the chief stew.

Below Deck fans already know that's a rule to live by, but apparently, this season's chef, Kevin Dobson, needed to learn it the hard way. He and chief stew Kate Chastain have bumped heads all charter season long, and it's all about to come to a head. As first teased in the season trailer, something -- or, more likely, someone -- drives Kate to leave the boat.

"It's a mother effin walk off!" she proclaims to ET at BravoCon, Bravo's first-ever fan convention. "I think it happens a bit later in the season. I get very frustrated and it takes me awhile to get that frustrated."

It seems safe to assume that Kevin may be the person who pushes Kate overboard, pun intended. When ET floated the theory that Kate eventually returns from her walk-off and gives Captain Lee Rosbach an ultimatum, Kevin or her, she admits that's "very close" to what goes down.

"I mean [Kevin's] certainly frustrated me," she offers. "That's true. I’m not really an ultimatum girl… unless you ask the last three people I dated."

Before that moment comes, though, there will seemingly be many more moments of Kevin vs. Kate, including on Monday night's episode, which finds "control freak" Kevin taking over service from Kate, much to her dismay.

"Kate understands food being served through a Burger King window," Kevin scoffs in a confessional. "She doesn’t understand how much work goes into it. So, I've almost had to take over that role of service. I shouldn't have to do this, because I should just be worrying about the food."

Check out ET’s exclusive sneak peek here:

Also mixing things up this season is the return of deckhand Rhylee Gerber, who steps in to replace Abbi Murphy. Abbi voluntarily left the yacht halfway through the season. When ET spoke with Kate, Rhylee’s return had not yet been confirmed, but she did promise that, "This deckhand is going to disrupt Ashton's perfect little bromance of a deck crew, which is, I think, necessary."

"This deckhand is a much harder worker than Abbi, and much more experienced," she adds. "So, I think it's an upgrade for everyone."

Of course, there are also a lot more charter guests to come, including former Real Housewives of Orange County star Alexis Bellino, who Kate teases is "off the Jesus juice and onto the fermented grape juice." But, Kate cautions, no charter guest will ever top Brandy, the woman who walked onto the yacht visibly inebriated -- and basically stayed that way for her whole charter -- earlier this season.

"There will never be, and there never has been, anyone on a yacht like Brandy," Kate says. "I just feel privileged that I got to experience it, honestly. She was so wild, she was amazing. She got evacuated off a beach in a clear kayak, in an emergency medical kayak. That’s not a thing, but it is now. While wearing -- she was wearing so many diamond bracelets. Ahh!"

Below Deck airs Mondays at 9 p.m. ET on Bravo.