Yes, I did read the OP, but perhaps I misunderstood. Here's my takeaway, and why I responded as I did:
Some channels do not have guide info, and the OP wanted to have "something" in the guide. The example shown created a 365-day long program-entry simply to show "something" in the guide. The link I posted—and information I excerpted—shows how to essentially achieve the same thing. However, using the custom tvc- tags as a fallback is a two-fold enhancement:
- Fallback data – Since the supplied title and description are treated as a fallback by Channels, they will always be present when there is no guide data. This is an improvement over the auxiliary XMLTV, since there is no need for a start/stop time, it is just omnipresent. Also, depending upon how long you created your
programmeelement for, you won't have to keep creating new XMLTV files when yourprogrammeends. - Can be superseded – If you use the fallback data, but then decide to add some guide data via XMLTV, it will be added to the guide when appropriate, but still show fallback data when there guide data is not present.
(A note about 1 above: The XMLTV DTD only states that a programme element must have a start attribute; the stop attribute is optional. The comments in the DTD indicate that the stop time should be as accurate as possible, and that it is one end of a half–closed interval. This means that the programme runs from start until just before stop. But, the specification seems to imply that the stop attribute is optional, and the guide program—in this case, Channels—should make the programme run until a subsequent programme with a later start is encountered. If one were to read the DTD in this manner, you could use any before–now time in start, and simply omit the stop, and have a similar situation to Channels' fallback data.)
The point I was trying to make in pointing out those tags for the playlist was that what the OP was trying to achieve could already be done, and without the need to create (and maintain) an additional file.
Of course, all of this could be moot if the OP is not using a M3U playlist as a source; but that was an assumption I made based upon the use of the accompanying XMLTV file. And since the OP never states what the source with the missing data is, I feel that was a safe conclusion. If @jdroberto wants to state what the source is and how this won't work, then I apologize for the noise.
The tvc- tags for the playlists are specific to each channel. They literally are channel specific. They are specified along with (among others) which logo to use for the channel, its name/callsign, and which channel number to assign when it is imported.

