Vikings' Bjorn Lothbrok has aged from a boy to a man in the last three seasons, and soon the warrior may start to sprout his first gray hairs.

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A fan of multi-year time jumps, the History Channel series may accelerate the storyline once more as season 4 hits midseason. Alexander Ludwig (Bjorn) recently posted a selfie from set, and fans were quick to notice the character's graying beard.

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A photo posted by Alexander Ludwig (@alexanderludwig) on Nov 12, 2015 at 9:19am PST

Unfortunately, there is no official confirmation regarding recent theories. Series creator Michael Hirst hasn't even given an exact time frame for the jump from the season 3 finale to the season 4 premiere.

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"Some time has passed," Hirst teased, according to The Hollywood Reporter. "The journey home took a little longer than they supposed. It hasn't been an easy run across to Paris or a straight run back. They'll have been away for a couple of years, something like that."

If Vikings is continuously renewed, Hirst is planning on putting the focus on Bjorn's travels in the Mediterranean. That being said, it wouldn't make sense for the series to dive too far into the future just yet.

Find out more when Vikings returns to the History Channel in 2016.