I bought an Arris SVG2482AC Modem/Router in June 2019 and soon discovered and was confirmed that BOTH USB ports were not working. No power for connected devices such as an external SSD. I was told that there will be a firmware upgrade in around September 2019.
Where can I find out more info.?
Those USB ports are there to provide power for your USB devices, not to provide data connections such as to an external hard drive. I've never seen those ports advertised for any other purpose:
Did you try charging a smartphone with either port?