When you change Date/Time preference, it is not respected in Service Portal
Steps to Reproduce
1. Login an instance with the Service Portal plugin installed
2. Open the page /$spd.do
3. Add the Widget "Data Table from Instance Definition" to a page
4. Click on the pencil icon to edit and select Table and Fields
5. Include the created or updated timestamp date fields
6. Change the instance settings clicking on the top-right gear icon from "Date/Time" to "Time Ago" and vice-versa
7. Load incident.list and check how the date is displayed in both cases
8. View the page /sp and check how the date is displayed in both cases
The Date/Time will change outside Service Portal but not in Service Portal.
This behaviour is by design in Service Portal and there is not plan to change it in current or near future releases. You can submit an Enhancement Request and Subscribe to this article to be notified in case of future updates.
Related Problem: PRB909690