Generate random timestamp taking into account shift to daylight saving time
You can create timestamp in SYSTEM timezone with:

FROM_UNIXTIME(timestamp_in_seconds) -- This is a number, not a datetime


To convert back to a timestamp you can use UNIX_TIMESTAMP function.

This sample demonstrate how to generate random datetime based on starting point. It give you only correct timestamps:

select FROM_UNIXTIME(UNIX_TIMESTAMP('2016-03-27 00:30:00') + rand() * 10000);