I have gotten that occasionally with my 721's. I usually have to do a reboot to get it to update.
If I just rebooted then I will have to wait for a bit for it to pull it off of 110.
However, the 721's have a "critical detection" circuit. The more important the guide is to you - the random generator might just generate the right number combination and NOT update the guide for another random amount of time.
Really!
My brother's aunt's uncle's wife's nephew told me this. He's a installer and knows what he's talking about!