
Samsung Galaxy Note 10.1
The latest firmware for Samsung Galaxy Note 10.1 (SHW-M486W) is M486WKAJML3 with Android 4.1.2 (Jelly Bean), released on January 2, 2014 for 1 region (CSC). Every official firmware build for SHW-M486W, 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/M486WKAJML3

SHW-M585D

SHW-M580D

SHW-M570S

SHW-M500W

SHW-M480W

SHW-M480S

SHW-M440S
You can find the firmware on the model: SHW-M486W page.
Yes, all firmware files for SHW-M486W are 100% official, original, and obtained directly from Samsung servers.
To flash SHW-M486W, 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 SHW-M486W.