Another post that is as much for my own note taking as anything else but, on the chance that somebody might find it useful, I decided WordPress would be better than Evernote.
When setting up MythTV I have previously followed the excellent UK-centric guides provided by Garry Parker at http://parker1.co.uk/. When it came to setting up the channels for Freesat I found his guide at http://parker1.co.uk/mythtv_freesat.php no longer worked for me in one small respect – the channel scanning. I did some digging around for Freesat frequencies and here are what I found that work for me on the Wirral.
I scanned with all four of these settings, leaving everything else at default and I now have a full set of satellite channels