S3 Fallback to analog when digital fails

Last night, I noticed that two of my channels were completely blank on the S3 (both tuners). I know they were working recently because I had shows recorded on those channels and I was still able to tune surrounding channels as well as premium (both SD and HD) channels. A reboot had no effect. I checked the old S1 Tivo and it was having no trouble at all with the analog versions so I figured that there was an interruption on the digital simulcast of those two channels. Unfortunately, the S3 doesn't seem to make any attempt to record from the analog channel when the digital signal is degraded or unavailable.

It would be nice if the S3 would attempt to record from alternate sources when available. This could come into play more often now that the same show could be showing on as many as 4 channels simultaneously. (OTA, cableHD, CableSD-digital, CableSD-analog)