
Samsung Galaxy Pocket Neo
The latest firmware for Samsung Galaxy Pocket Neo (GT-S5310) is S5310XXANI1 with Android 4.1.2 (Jelly Bean), released on October 20, 2014 for 4 regions (CSC). Every official firmware build for GT-S5310, 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/S5310XXANI1
All 16 builds in our database run Android 4.1.2 (Jelly Bean). The newest build, S5310XXANI1, was released on October 20, 2014. No new build has appeared for 146 months, so regular updates for this model have most likely ended.
Box codes of GT-S5310 for different colors and markets. Firmware is chosen by the model code GT-S5310 and your region (CSC), not by the SKU.

GT-S7508

GT-S7500T

GT-S6812

GT-S6500L

GT-S5690L

GT-S5670

GT-S5570I

GT-S5303
The newest firmware for GT-S5310 runs Android 4.1.2 (Jelly Bean): build S5310XXANI1, released on October 20, 2014.
The latest build for GT-S5310, S5310XXANI1, was released on October 20, 2014 (12 years ago).
GT-S5310 has had no new firmware for 146 months, so regular updates have most likely ended.
Yes, all firmware files for GT-S5310 are 100% official, original, and obtained directly from Samsung servers.
To flash GT-S5310, 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 GT-S5310.