Samsung has started rolling out the March 2020 security patch to the Galaxy M30s. It is currently rolling out in India. The software version of this update is M307FXXS2ATB3. The size of this update is 119MB.
The Galaxy M30s will be upgrading to One UI 2.0 in April 2020, according to Samsung’s Android 10 roadmap.
If you want to download the update manually, just go to device Settings, then tap on the Software update and go to Download and install option.