Static IP change

Recentlly, last night I had an issue with my comcast modem (SMC).   The support rep could not get it to work whether using my static IP's or plugged directly in using DHCP.

This morning DHCP directly off the SMC is working fine.   Computers and units that run off the static addresses do not work(note most of this are routers etc, not actual PC's).    I checked the IP of the SMC device and that has changed as well.

Does Comcast ever change your static IP's or do I need to have someone reprogram my SMC device properly? 

Thanks,

Pat