I happened again last night about 6:00pm, guide extended less than 2 days. And of course the local OTA sub channel data is also gone so I cannot even see what is on in the next hour.
I did a Check Switch & noticed neither the "Alternate" or "Super Dish" were selected. Just to confirm, your "Alternate" was already selected by default?
Yes "Alternate" was already selected. Adding "Super Dish" seems to have done the trick. I don't think you can hurt by selecting both. If different issues arise, backtrack and try again. I have still not had any issues since trying this.