said by horseshoe:Did your modem trigger off and boosted to the 8 after you checked?
Whether the modem reboots totally depends on what was needed to be done during the channel adds and how the equipment involved is configured.
I've seen where the channels were just added and the modem picks them up without rebooting. On the other hand I've seen where the CMTS needs to be rebooted for the channels to be turned up properly, that in turn causes all the modems to reboot and resync which can take 15 minutes to an hour. Some fall in between where the modem or CMTS didn't need to reboot, but the connection was interrupted for a few moments while the modem switched channels.
The only way for end users to really know is to check their modem diagnostic pages and compare them to what they previously had.