In my enviornment I have equipment located throughout several different timezones. To counter this and to make event correlation easier we have set all equipment including our NPM server to use UTC time.
The one problem with this is that we still need to alert local staff based on their local timezone. For example a technician in New York needs to get SMS pages from 5:00 PM to 9:00 AM. It is easy enough to just do a one time conversion from Eastern time to UTC however the problem of Daylight savings time comes into play.
What I think would be a great feature would be to actually include the timezone in the Time of Day tab of the advanced notification manager. This way one could set the alarms to localtime so you would not have to go back into each alert action and modify time ranges to account for daylight savings.