on how to safely identify the correct firmware version for this specific model?
If your Huawei E303s-1 is in (where it acts as a network adapter and opens a web page automatically), you can update it directly from the interface: huawei+e303s1+firmware+update+free
Updating the firmware on a Huawei E303s-1 (HiLink 3G USB Modem) is a common way to improve connection stability, unlock it for other carriers, or switch between "HiLink" (web interface) and "Stick" (dial-up) modes. Firmware Update Overview on how to safely identify the correct firmware
Navigate to to find your current firmware version. Step 2: Where to Find Free Firmware Downloads Step 2: Where to Find Free Firmware Downloads
Mina slid the modem back into its case and placed it beside a framed photograph of her grandfather on the shelf. The update hadn’t just revived a piece of hardware; it had stitched a little more of his life into hers. The next morning, she took the modem with her on the train, a talisman of connectivity and memory.
: If the update fails, the modem may become "bricked" (unusable). You might need the "needle method"