Yeah, if you reduce your course from full credit, you have to inform the DSO and apply for economic hardship, then only your F1 status will be maintained. Just getting TPS approved does not allow you to enjoy the benefits of reduced course load.

See this-
Are experiencing severe economic hardship as a direct result of the damage caused by the earthquake of April 25, 2015.

So, do not get confused, better talk to the DSO.