ATT put fiber up in Emerald Hills and Sonic leases it from them. I had it installed yesterday, it works great. The only issue is that because the modem/wifi combo is leased from ATT and you need an ATT account to enable advanced features such as parental controls, port forwarding, etc., those features are not available if you buy through Sonic. You will need to buy your own router if you need those features.
In the last month, Sonic has been sending postcards advertising gigabit fiber to my house in the Selby neighborhood (near Woodside and Alameda). I assumed it meant that it was available, but when went to sign-up I found it was a pre-order. Still, I figured it must not be too long if they are advertising and then I found this thread where some pre-ordered years ago.
Is Sonic fiber available to anyone in Redwood City yet? If so, where? If not, has anyone gotten a commitment date for availability?
I'm interested in this too. AFAIK, Sonic is not leasing fiber from AT&T. Instead, AT&T wholesales fiber access to Sonic, which Sonic then resells to you. When you switch from AT&T to Sonic, Sonic likely has to pull a new drop to your house and swap out the fiber router or ONT (fiber modem). They can probably reuse any in-home copper wiring that was installed for the AT&T service.