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Then, I'm sure someone could probably write new firmware to use the Freeview EPG data embedded in channel stream. Or maybe IceTV Guide will continue.
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Hard to work out what you mean by "Freeview EPG".
If you mean the MHEG-5 Freeview EPG that was launched by Freeview, then that has a limited lifetime (
finishes November 2017) and is DRM protected, so it can't be accessed without the appropriate keys from Freeview.
The Freeview Plus EPG isn't in the broadcast stream. It will continue, but it also appears to be tied up with DRM.
The EIT EPG data in the broadcast stream is really the only EPG that's freely available, but it lacks some useful metadata that's in the IceTV EPG, like reasonably reliable repeat markup.