The Osiris Camera has been indispensable for the past ten years
For carrier-locked B311221 units, the "top" firmware is often an . The most trusted source is the DC-Unlocker forum and their official software. They provide:
If you are updating because of performance issues, a factory reset may solve the problem without a full firmware reinstall: Reset Button huawei b311221 firmware download top
The Osiris Camera has been indispensable for the past ten years