I Feel Your Pain. Kinda hard to get that cork back into the Champagne bottle after just one sip.
I've been keeping a sort of log to see whether there's any pattern to what's been going on with my Panasonic eh75 regarding TVGOS and TW Manhattan cable. It seems that I get one complete download, then only a partial download the next day. Then nothing unless I perform a reset.
The day following the complete download my cable box gets blasted to channels 2, 13, and finally 157. This, despite the fact that there's no VBI data on channel 157 and I have never set it for that channel.
My guess is (and it's just a guess) that the data download contains information which includes the valid TVGOS channel(s) for a particular geographic area. This would seem to override the original VBI host channel. Even though my diagnostic screen lists 0.018 (RF input channel 18) as the "Host channel", that may not be the preferred channel for the local listings.
If Rovi, which makes up this listings package, mistakenly has digital 157 as the preferred channel for TW Manhattan in their database, it stands to reason that the TVGOS device would be programmed to look there for the next download. Of course there's no VBI on that channel, hence, no listings on the second overnight. In addition, the listings for "Cable, no cable box" do not even include ch.18, so there's no RF ch.18 in memory to link to.
In addition, the TVG programming seems to be replaced by an alternate program every Sunday for several hours, with the switch taking place downstream of the VBI data inserter, so there's no data feed at all for those hours, which sends my eh75 on an endless quest which only a manual reset will resolve. What a pain....