When IST is at 12:30 PM, the PDT is at 12:30 AM, but today when IST was at 12:30 PM, the PDT is at 11:30 PM. I just saw because new daily leetcode challenge is not uploaded at the usual time of 12:30 PM IST. Can anyone tell me how is that possible?\n\nIST: Indian Standard Time\nPST: Pacific Standard Time\nPDT: Pacific Daylight Time\nPT: Pacific Time \n\nEdit 1: I know that leetcode uses PDT and I also know that IST to PDT has difference over 12.5 hours but now all over the internet it is of 13.5 hours.\n\nEdit 2: Okay now I get it why there is sudden change. Those who are having the same problem refer [here](http://www.differencebetween.net/miscellaneous/difference-between-pst-and-pdt/). In the article it is written that USA in summer uses PDT while in winter they use PST. And the absolute difference between PST and PDT is 1 hour. That is why according to IST, daily leetcode challenge will be uploaded 1 hour later in winter in comparison with summer time.\n\nSummer: [May - Oct]\nWinter : [Nov - April]\n\nThe new thing that I learnt today is PT uses PDT in summer and PST in winter. Next time you see this 1 hour lag then the answer is there is change in season ;)

When IST is at 12:30 PM, the PDT is at 12:30 AM, but today when IST was at 12:30 PM, the PDT is at 11:30 PM. I just saw because new daily leetcode challenge is 