
Samsung Galaxy S4 Mini 16GB (U.S. Cellular)
The latest firmware for Samsung Galaxy S4 Mini 16GB (U.S. Cellular) (SCH-R890) is R890TYUBPD2 with Android 4.4.2 (KitKat), released on April 26, 2016 for 1 region (CSC). Every official firmware build for SCH-R890, newest first: one row per build with all regions (CSC) that received it.
Each firmware build has its own page at https://samfirm.shop/build/{PDA}, where {PDA} is the build number from the list above. Example: https://samfirm.shop/build/R890TYUBPD2
All 4 builds in our database run Android 4.4.2 (KitKat). The newest build, R890TYUBPD2, was released on April 26, 2016. No new build has appeared for 127 months, so regular updates for this model have most likely ended.

SCH-R970X

SCH-L710

SCH-I939D

SCH-I435

SCH-I545
The newest firmware for SCH-R890 runs Android 4.4.2 (KitKat): build R890TYUBPD2, released on April 26, 2016.
The latest build for SCH-R890, R890TYUBPD2, was released on April 26, 2016 (10 years ago).
SCH-R890 has had no new firmware for 127 months, so regular updates have most likely ended.
Yes, all firmware files for SCH-R890 are 100% official, original, and obtained directly from Samsung servers.
To flash SCH-R890, you need to download the appropriate firmware, put your device into Download Mode, and use the Odin tool to load the BL, AP, CP, and CSC files.
Downgrading is only possible if the bootloader version (binary bit) of the old firmware matches the current one. Always check the binary version before flashing SCH-R890.