Thanks for the clarification, much appreciated for all the work.
To filter for services transmitted on DVB-S2 is easier, but they may be HD, SD, or without video at all.
Yes, DVB-S2 filter implementation would be good, as the provider I am interested has all HD services/channels, on DVB-S2 and sd on DVB-S, but as per your suggestion I have simply used the grep command and filter the channels file, like this.
Quotegrep HD channles-file > sorted-file
Cheers