There is no such time zone as “EST”. Or “EDT”. Time zones are DST independent. The time zone is “ET”. Period.
You don’t hear people talking about UDTC/USTC. It’s UTC. Or GMT for the old-school folks in the crowd. Zulu is zulu. Don’t mess with it.
Please, I beg you, do not programattically collect and store DST information. States vary DST behavior. Nations vary DST behavior. Nations within States vary DST behavior. Read the Wikipedia post on DST to understand how fucked up it is- worldwide.
Rant for the day. We now return you to your regularly scheduled web….