More than a couple of our vendors have been frustrated by my insistence that they properly support daylight saving time. Both switch overs have their own set of unique potential problems but if a vendor has an API as part of their product and we're going to build automation on top of it, this twice a year undefined behavior generator isn't acceptable. It surprises me how many companies seem to have an severe allergy to using UTC or even including TZ data with their time/date data.