Some firmware versions are known to break bridge mode, causing it to fail when connected to external mesh routers like Linksys or ASUS. Ensuring you are on the absolute latest version is the first step recommended by Three Community Wi-Fi Band Steering:
: Note that hardware modifications for external SMA ports generally do not require software or firmware adaptations, though you may need to select "internal antenna" in the login page to ensure the modified path is used. Are you looking to a specific device, or are you interested in extracting the firmware for research purposes?
: Expert users have noted that for its high-end chipset (Snapdragon X62/X65), the factory firmware doesn't offer the deep level of control found in third-party firmware like OpenWrt .