It's been about a week and a half since I had my shifted clock issues, and nothing more has cropped up on that front. I suspect it had something to do with the channels I watched the nights it happened, NBC (25.1) and The CW (25.2), as they are the ones that for some time always appeared shifted an hour in the guide with every DST change. Perhaps the discontinuation of TVGOS had some influence or effect on them, I don't know. I definitely lost my TVGOS, but it still says the time has been acquired by TVGuide, and the clock is grayed out. It remains on time, so I've decided to not do a factory reset but wait and see if anything else happens. After several posters discussed it, I have been checking out the PSIP clocks my DVR is receiving out of curiosity; here's what I saw:
PSIP (5) (Anyone know what that number means?), elements: 36 (Is that supposed to be how many stations' clocks it's receiving? I have only 19 IDENTs listed, so it doesn't seem to match up.)
Early Sunday afternoon--8 were under +/-10, 3 were within the +/-10-20 range, 4 went over (22, 23, 40, and 52--I think they were all negative), and then there were 4 outliers: -979, +225, +618, and +750
Sunday evening, about 12 hours later--all but one of them had shifted to be more positive (by the same amount, oddly: 3): 8 were +/-10, 5 were +/-10-20, 2 went over (37 and 52), and the outliers were -976, +228, +621, and +753
Monday evening, another 24 hours later--7 were +/-10, 5 were +/-10-20, 3 went over (23, 43, and 54), and the outliers were -990, +220, +630, and +762
Additionally, it took a week but I now have PSIP guide data that goes out longer than a few hours. Such a nice surprise Friday night to see 24 hours' worth of listings for all but 2 channels (but those channels never provided information through TVGOS, either). About half of those continued on for another 12 hours beyond that point.