I came across this simple sentence:
He will be back soon. 他很快就会回来的。
I understand that the 就 is expressing earliness, but what is the 的 doing here? In the textbook 新的中国 it doesn't say 的 is part of the 就 construction, or on the allgrammar wiki here https://resources.allsetlearning.com/chinese/grammar/Expressing_earliness_with_%22jiu%22
Is 的 turning the 会回来 into a sort of adjective? Since 会 is an adverb I expected it to be followed only be the verb 回 with the directional complement 来 without the 的. Any help would be appreciated.