Question - why do you believe Park Dang-gu will be leader of Songrim when Part 2 begins? I don't see anything…
It's the clothes/look of the two. Park Jin is seen in commoner clothes with a shorter hair cut now while Danggu now was wearing clothes that seemed to represent a higher position. Specifically, the robe he's wearing. We see the leaders wearing those types of robes in AoS. Plus, his hair style isn't playful anymore. It's more serious. I hadn't heard about the belt theory until now. But reading about that makes sense too. It seems like there's definitely been a time leap - probably around 5-6 months or so I would assume. Let's of time for Danggu to take over the role of a leader. He was preparing to become one in AoS part 1 anyways.
My guess is that either Park Jin decided to step down because of what happened with Uk, Naksu, and Jang Kang - loosing and almost loosing them OR he was forced to step down. Most likely he was forced due to the friction between him and the other leaders because of his relationship and history with Uk and Jang Kang.
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I hadn't heard about the belt theory until now. But reading about that makes sense too.
It seems like there's definitely been a time leap - probably around 5-6 months or so I would assume. Let's of time for Danggu to take over the role of a leader. He was preparing to become one in AoS part 1 anyways.
My guess is that either Park Jin decided to step down because of what happened with Uk, Naksu, and Jang Kang - loosing and almost loosing them OR he was forced to step down. Most likely he was forced due to the friction between him and the other leaders because of his relationship and history with Uk and Jang Kang.