[@Ammokkx]

The emergence of the Fleet of Fog in 2039 is still part of the history. 2049 is the year that the last major battle between humans and the Fleet of Fog occured, which is why it is mentioned in Shinano's Bio, resulting in an absolute defeat for humanity.

There are certain ships, such as the Yamato, that I am reserving for the purposes of the plot. If you really want the Yukikaze, I can make it work without much difficulty.