A: Generally, no. The 2021 bootloader prevents downgrading to versions older than 2020 to prevent security rollback attacks. Attempting it will result in a "Image validation failed" error.
In 2021, FiberHome released several firmware iterations for the SR120A series aimed at improving stability and security protocols. The version numbers typically follow a structure like RP.rls1.2610.10 or similar, often starting with V3.0 or V4.0 depending on the hardware revision. fiberhome sr120a firmware 2021
Key Characteristics of 2021 Firmware:
Before hunting for an update, you must know what you are running. A: Generally, no
Step-by-step check:
Example of a 2021 build string:
V5.0.2_20210815_GPON_ONT (The 20210815 indicates August 15, 2021). Example of a 2021 build string:
V5
If you see 2020 or 2019, you are overdue for an upgrade. If you see 2022 or later, you are already past the 2021 baseline.