
Samsung Galaxy S Relay 4G (T-Mobile)
The latest firmware for Samsung Galaxy S Relay 4G (T-Mobile) (SGH-T699) is T699UVBOH1 with Android 6.0.1 (Jelly), released on October 5, 2015 for 1 region (CSC). Every official firmware build for SGH-T699, 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/T699UVBOH1
All 2 builds in our database run Android 6.0.1 (Jelly). The newest build, T699UVBOH1, was released on October 5, 2015. No new build has appeared for 134 months, so regular updates for this model have most likely ended.

SGH-I927

SGH-S730M

SGH-T999N

SGH-T989D

SGH-T859

SGH-T599V

SGH-I757M

SGH-I747
The newest firmware for SGH-T699 runs Android 6.0.1 (Jelly): build T699UVBOH1, released on October 5, 2015.
The latest build for SGH-T699, T699UVBOH1, was released on October 5, 2015 (11 years ago).
SGH-T699 has had no new firmware for 134 months, so regular updates have most likely ended.
Yes, all firmware files for SGH-T699 are 100% official, original, and obtained directly from Samsung servers.
To flash SGH-T699, 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 SGH-T699.