The new software update for Galaxy S10 is rolling out in the Czech Republic with firmware version G973FXXSBFUF3. We can expect the new OTA update to reach more regions in the next few days. This is a minor security patch update and does not brings new features, performance boost, or UI changes. As of now, Samsung has not detailed the July 2021 security patch. So, we don’t know, which security and privacy related bugs are getting fixed. Usually, the company details the latest security patch in the first week of the month.  Samsung Galaxy S10 users who have not received the new OTA update yet, can manually check the status by heading to Settings » Software updates. As the security patch update has just started rolling out, it may take a few days to reach all the Galaxy S10 units. [source]

Samsung Galaxy S10 becomes the first phone to get July 2021 security patch update - 46