X1 PREFERRED PRO+ provisioning issue: only getting 30Mpbs download

I recently switched from Comcast business back to Xfinity to get the 600/15Mbps download.  However, after the switch, when I ran the speed test, the most I got is only 30/16Mbps.  How do I know whether Xfinity has changed the provisioning?

I have a new cabel modem Netgear CM1100 to handle the new bandwidth.