Changing this interval even to 5 milliseconds doesn't change that the requests are made just once every 24-hours. Currently it's like this:

Monday - update at 9:00 (the time gets saved in user preferences)
Tuesday - turn on PC at 8:55 (it's not 24 hours yet, so no update check, schedule update check 24 hours + 2 minutes from 8:55 to Wednesday 8:57 - no update check for almost 24 hours)

This is scenario in a case Brackets are not restarted entire day.