I think it makes sense actually? The simultaneous attacks on Malaya (as was) were on Dec 8 local time so Dec 7 in UTC-10 should show as Dec 8 local in UTC+8 or +10?
Do posts on here even come with offsets? I don't see anything after the Z in the createdAt field.
Everything being UTC and converted makes more sense, but showing the posters' timezone too is kind of funny.
Who can say, it was 80+ years ago after all.
Glad I don't have to think about this much, being in UTC a lot of the year. (less than half, I just checked)