
Samsung Galaxy Ace4
The latest firmware for Samsung Galaxy Ace4 (SM-G316HU) is G316HUDDS0AQD1 with Android 4.4.4 (KitKat), released on April 3, 2017 for 4 regions (CSC). Every official firmware build for SM-G316HU, 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/G316HUDDS0AQD1
All 24 builds in our database run Android 4.4.4 (KitKat). The newest build, G316HUDDS0AQD1, was released on April 3, 2017. No new build has appeared for 116 months, so regular updates for this model have most likely ended.

SM-G316MY

SM-G313MY

SM-G318MZ

SM-G310HN

SM-G5109
The newest firmware for SM-G316HU runs Android 4.4.4 (KitKat): build G316HUDDS0AQD1, released on April 3, 2017.
The latest build for SM-G316HU, G316HUDDS0AQD1, was released on April 3, 2017 (9 years ago).
SM-G316HU has had no new firmware for 116 months, so regular updates have most likely ended.
Yes, all firmware files for SM-G316HU are 100% official, original, and obtained directly from Samsung servers.
To flash SM-G316HU, 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 SM-G316HU.