'Chicago Fire' season 5 spoilers, plot news: Miranda Rae Mayo promoted as series regular, story to explore Stella and Severide's relationship

Newbie Miranda Rae Mayo will get more screentime in "Chicago Fire" as she has been promoted as a series regular for the upcoming season 5.
Mayo, who plays the role of firefighter Stella Kidd, first appeared in the show as a new member of Firehouse 51. As fans know, Stella had previous ties with Dawson (Monica Raymund) and Severide (Taylor Kinney) when she joined the department. Severide tried to show his interest for Stella before, and they decided to take their relationship to a new level in the finale. Stella finally had the courage to leave her husband Grant (Guy Burnet) to be with the man she really loves.
Fans were left hanging in the fourth season's final episode as Grant discreetly went to Stella's apartment, grabbing a knife while she was sharing an intimate moment with Severide in the other room. After that cliffhanger, there are speculations that the season 5 plot will explore their budding relationship and how it will affect the people around them.
Showrunner Matt Olmstead recently caught up with The Hollywood Reporter where he discussed how Stella will play a key role in the fifth season. "[It] all leads towards to Severide and Kidd having to take a break," he explained. "But, all the while, hopefully convincing the audience, as we're convinced, that they're really made for each other. They're really similar and we want to create a sense of, it would be great for them to be together."
In terms of fresh faces to join the show, Olmstead mentioned that adding a new character is still not in their plan. Their goal is to tie all the loose ends first, and once everything has cleared out, a cast member might be added in the future.
As of the moment, the network has yet to announce a definitive premiere date for "Chicago Fire" season 5, but it will surely return sometime in Fall.