I noticed that while FiOS is carrying KVCR PBS (San Bernardino California) on HD channel 524, the feed is a mirror of the SD channel and not in high definition. It seems odd to have a channel listed in HD and yet it's not the actual HD feed of the channel.
1. it could be that the program that is currently playing is not available in HD. It may be a HD channel but if the program is not filmed in HD, it wont be broadcast in HD.
2. It could be that the channel is currently having problems with the HD broadcast and instead of just have a blank channel they are just putting the SD broadcast up so at least there is something on the channel.
3. Same as 2 but on the Verizon side. Verizon may not be getting or having problems with the signal that they are getting and while they work on it they just duplicated the SD broadcast.
If it is 1, then when an HD program is on, you will get the HD. If it is 2 or 3 it will likely correct itself once Verizon or PBS fixes the problem with the signal. Likely they already know of the issue as normally the SD feed is not sent to the HD channel so the fact that you have a pic at all means that someone made the change, therefore they know about it. But if you want, you can call tech support and report it. They will take a report and send a ticket to the broadcast center for them to inspect if they dont already know about it. But with the difficulty in calling tech support I wouldnt worry about it unless it lasts several days.