The article really is worth a read if you build complex systems. My takeaway from this is that you shouldn't schedule maintenance work during "weird" times.

Had they not been deploying new code on leap day (UTC), the outage would have been substantially less severe. Code that uses dates and times will have bugs, because it's hard. Don't complicate things further.

So from now on, no more leap day, daylight savings time, or new years maintenance. It's worth postponing a day just in case.