Changes in Daylight Savings Time

Most of you are prob­ably already aware of the legis­lat­ive change affect­ing day­light sav­ings in North Amer­ica. In any event, the nub from an internal note:

The U.S. Energy Policy Act of 2005, passed by the U.S. Con­gress July, 2005, exten­ded Day­light Sav­ing Time (DST) in the U.S. by approx­im­ately four weeks. This change was sim­il­arly adop­ted by the Gov­ern­ment of Canada in order to har­mon­ize time zones across North Amer­ica. As a res­ult, begin­ning in 2007, DST will start three weeks earlier on March 11, 2007, and end one week later on Novem­ber 4, 2007, res­ult­ing in a new DST period that is four weeks longer than pre­vi­ously observed.

(slight cor­rec­tion by the way — time is gov­erned by the provinces in Canada — see for example the rel­ev­ant Ontario reg­u­la­tion).

Apart from chan­ging your clocks, you should make a note of whether any patches or updates to your com­puter sys­tems are required. I know I’ve already seem some traffic on how MS Out­look and Black­berry stuff might need patches as a res­ult of the change. You might also want to high­light this when mak­ing appoint­ments dur­ing the changed period.

In addi­tion to that, there are also some art­icles, such as the one in Tech­no­logy Review, that warn of other poten­tial glitches:

Cameron Haight, a Gart­ner Inc. ana­lyst who has stud­ied the poten­tial effects of the daylight-saving bug, said it might force trans­ac­tions occur­ring within one hour of mid­night to be recor­ded on the wrong day. Com­puters might serve up erro­neous inform­a­tion about mul­tina­tional tele­con­fer­ence times and physical-world appointments.

”Organ­iz­a­tions could face sig­ni­fic­ant losses if they are not pre­pared,” the Inform­a­tion Tech­no­logy Asso­ci­ation of Amer­ica cau­tioned this week.

Dave Thewlis, who dir­ects Cal­Con­nect, a con­sor­tium that devel­ops tech­no­logy stand­ards for cal­en­dar and schedul­ing soft­ware, said it is hard to know how wide­spread the prob­lem will be.

That’s because the world is full of com­puter sys­tems that have par­tic­u­lar meth­ods for account­ing for time of day. In many, chan­ging the rules around day­light sav­ing is a snap, but in oth­ers, it may be more complex.

”There’s no rule that says you have to rep­res­ent time in a cer­tain way if you write a pro­gram,” Thewlis said. ”How com­plic­ated it is to imple­ment the change has to do with the ori­ginal design, where code is located.”

…and don’t for­get inter­na­tional stuff:

Also, the change ori­gin­ated in the United States and is being fol­lowed in Canada, but not most other nations. That could befuddle con­fer­en­cing sys­tems and other applic­a­tions that run in mul­tiple coun­tries at once.

Update: A great and con­cise art­icle on slaw with more details and bet­ter links on the changes in DST.

related:

1. cana­dians  —  as bad as the chinese (almost)
2. Wiki­al­ity
3. Of Search Engines and Com­pet­i­tion (Part II)
4. bell’s chief brand officer to speak