Samsung Galaxy J3 Top
The latest firmware for Samsung Galaxy J3 Top (SM-J336AZ) is J336AZTUSDAVK1 with Android 8.0.0 (Oreo), released on December 13, 2022 for 1 region (CSC). Every official firmware build for SM-J336AZ, 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/J336AZTUSDAVK1
All 9 builds in our database run Android 8.0.0 (Oreo). The newest build, J336AZTUSDAVK1, was released on December 13, 2022. No new build has appeared for 47 months, so regular updates for this model have most likely ended.

SM-J337A

SM-J330N

SM-J327VPP

SM-J320VPP

SM-J326AZ
The newest firmware for SM-J336AZ runs Android 8.0.0 (Oreo): build J336AZTUSDAVK1, released on December 13, 2022.
The latest build for SM-J336AZ, J336AZTUSDAVK1, was released on December 13, 2022 (3 years ago).
SM-J336AZ has had no new firmware for 47 months, so regular updates have most likely ended.
Yes, all firmware files for SM-J336AZ are 100% official, original, and obtained directly from Samsung servers.
To flash SM-J336AZ, 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-J336AZ.