The pair have overcome a turbulent year in which they came close to divorcing when Jimmy (Nick Miles) left Nicola (Nicola Wheeler) for ex-fiancée Kelly Windsor (Adele Silva), who exploited his amnesia for her own ends.
Blackburn claimed that Nicole and Jimmy's happiness will be short-lived though, as someone or something from their past returns to "stir things up".
"Jimmy and Nicola, there's some great adventures for them coming up," Blackburn said in a 2012 preview video. "I think Nicola's going to put her foot down on certain issues.
"There's a couple of surprises coming up and maybe a wee blast from the past just to stir things up a little bit."
Blackburn also hinted at what the next year holds for other Emmerdale couples Katie (Sammy Winward) and Declan (Jason Merrells) and The Bartons.
"Declan, as everybody can see, is a complete emotional idiot," he commented. "I think the one thing Katie's not going to do is make any of the same mistakes of the past. We're gonna see a much, much feistier, stronger Katie."
On the Bartons' recent relationship troubles and actor James Thornton's upcoming departure, Blackburn continued: "John's been through hell and back, there's a long way to go but I think there's a chance for them [before he leaves].
"They're gonna find happiness, the trouble is it might just be a brief fleeting moment."
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