Correction! There are still seven muxes in London. There is local stuff on Channel 35. I found a lot of out of date info on the web before finding digitalbitrate.com which monitors what is on air today.
That doesn't solve my problem, though. The more I look, the worse it gets. I now realise I am missing lots of recent additions to the channel lineup, and still have many stations that are no longer operating.
This is what happens when I retune:
On the Settings page, I press the Tune Channels button.
I check that all the frequencies and channel numbers are correct for my area for today, and press the Start Tuning button.
I confirm by pressing Start Tuning again on the pop-up.
I watch the tuning process and notice that all muxes are found as the number of TV and Radio channels are listed for each.
When the tuning process finishes, I read the whole list of station names that have been found, including all sorts of new stuff (BBC3HD, Great Movies, etc) and no old stuff (Forces TV, etc).
Then I press the Set These Channels button at the foot of the list of station names.
The pop-up warns these will replace all currently tuned channels and that the guide will be emptied and repopulate over the next few minutes.
I press the Yes Update To These Found Channels button.
At this point the Guide reverts to its previous condition exactly. No new stations are displayed in the guide. No old stations are removed from the guide. And the guide is not cleared and does not update until the next scheduled update time. After the scheduled update (or a manual one) still nothing changes.
In case it matters, I am recording to a network drive, and had to adjust database file permissions to get it to work in the first place, and still on v1.0.4 because I can't get v1.0.5 to work after updating.
I would like to say that I think this software is fantastic, and it's free, and is now my main recording method. I am just trying to chase down this small snag in an otherwise brilliant system. So thank you again to lc200.