ARRIS SURFboard SB6183 DOCSIS 3.0 Cable Modem

Why doesn't COX of Wichita Kansas not fully support all the downstream channels of this modem? I was fortunate enough to have them upload the latest software (SB6183-9.2.0.0-GA-04-37-NOSH) and the modem went from 4 to 8 downstream bonded channels. If COX doesn't fully support this modems full capabilities - 16 Downstream Channels - then they should not recommend this modem for their networks.