I thought they based in China and use their time zone. But doesn't look like this is the case?
Ali probably assume Kiwis are either busy black Friday shopping instore or busy working during the day.
It's based on US Pacific Time (PST, UTC-8 hours)
Yeah AliExpress follows US Pacific Time. You'll find that the hours changes between 7pm and 8pm and 9pm due to daylight savings time changes in both countries.