Timestamps are always GMT-5
Simple bug at the timestamps in the Dashboard's Activity details. The list when you click the eye icon shows me timestamps that are 7 hours behind my local time and of course my student's local time.
Does your end of day to continue your streak roll over at the correct time for you?
If you go here: https://www.duolingo.com/users/FrankWilkin and search for "timezone" does it display the correct zone? My Dashboard timestamps display correctly so I've always assumed that they were tied to your what your account timezone is.
The bug only exists in Dashboard. And more specificly at the Activity details' lessons list wiht XP.
The timestamps in the activity details are displayed in your student's local time. I took a peek at your student's timezone and it looks like they are indeed in GMT-5. If this is not correct, feel free to shoot us an email at email@example.com with the timezone your student should be in.