Supernatural will be ending its fifteen season run this fall, with the final episodes set to begin airing on The CW on October 8th. (The series finale will air on November 19th.) Ahead of the "beginning of the end", series co-star Jensen Ackles – who, along with Jared Padalecki, plays one half of the monster hunting sibling duo Sam and Dean Winchester – sat down for an interview on Michael Rosenbaum's podcast Inside of You… and during their conversation, Ackles revealed that he doesn't think the season 15 finale will be the last we see of Sam and Dean.
I’ve always thought that there’s a possibility of five years down the road, getting the call saying, 'Hey let’s do a little short order action for a streaming network' and bringing it back for six episodes. I do feel like this isn’t the long goodbye right now. I feel like this is, 'Let’s hang this in the closet for now, and we’ll dust her off down the road a bit.'"
So basically, he feels like this is a break from Supernatural rather than a retirement from the show. It does make a lot of sense that he and Padalecki would need a break after fifteen years.
Ackles told Rosenbaum that he will be keeping the Winchesters' '67 Impala safe, and while he'll be making improvements like adding air conditioning and a functional radio, he'll mostly be leaving it the way it is, keeping the creak in the doors and the splits in the seats.
He also mentioned that genre icon Bruce Campbell was almost brought onto the show a couple seasons ago. And as cool as it would have been to see Sam and Dean interact with Bruce Campbell, the plan for him wasn't quite right. The creative team wanted Campbell to replace Jeffrey Dean Morgan as Sam and Dean's dad John Winchester, who was absent from the show for a decade before making an appearance in season 13.
Ackles told Rosenbaum,
They actually went out to Bruce Campbell to play Present-Day Dad (in season 13). That was the only person that they wanted. Ultimately, they couldn’t make it happen, whether it was [because of his] schedule or whatever. So they kind of threw their hands up in the air, and [were] like, 'Well, maybe we can just age Jeff up and have him come back and play an older version of himself.'"
For some reason, the producers felt it would be odd to have Ackles and Morgan sharing the screen as father and son in season 13, since Morgan is really only twelve years older than Ackles. But that wasn't an issue in the early seasons, so I'm not sure why they felt it would be an issue when the character came back. Things worked out the way they should have; it's good that Morgan got to play John Winchester one last time before the show comes to an end.
Maybe Bruce Campbell can play a different character in a revival season down the line.