Yes, indirectly. The OLT queries the ONT's software version. If it reports V300R016 instead of the ISP's V300R013, it may flag your device. Usually, they ignore it unless you have service issues.
Based on community testing (4PDA, GPON Forum, 2023–2025 data): huawei hg8321r firmware download
| Goal | Best Firmware Version | Hardware Compat | |------|----------------------|----------------| | Unlock web admin + bridge mode | V300R016C10S115_Ultimate | 10C3.A, 49FD.A | | VOIP stability (SIP) | V300R017C20S135 | 17FD.A | | Security patched (no backdoor) | V300R018C10S207 | All hardware revisions | | Chinese ISP (China Telecom) | V300R013C10S112 (stock) | 10C3.A | | Russian ISP (Rostelecom) | V300R016C01S103 | 1C3.A | Yes, indirectly
Note: R018 firmwares remove the Telnet backdoor, making future unlocking harder. Only flash R018 if you never plan to modify settings again. Huawei provides a Windows utility called ONT Upgrade
Huawei provides a Windows utility called ONT Upgrade Tool (v500 or v800). It requires a .bin file. This tool is the only safe way to flash.