https://mirror.math.princeton.edu/pub/ddwrt/betas/2022/01-10-2022-r48075/ubnt-unifi-ugw4-usbboot/?C=N;O=A
Index of /pub/ddwrt/betas/2022/01-10-2022-r48075/ubnt-unifi-ugw4-usbboot
https://mirror.math.princeton.edu/pub/ddwrt/betas/2018/11-17-2018-r37736/ubnt-unifi-ugw4-usbboot/?C=D;O=D
Index of /pub/ddwrt/betas/2018/11-17-2018-r37736/ubnt-unifi-ugw4-usbboot