I imagine it means the box has been manually tuned using a dual dish install somewhere in Ireland. This will have two lnb's on on 19.2E (Ka band) and the other on 28.2E (Ku band). There's no other way I can think of that you have saorsat channels in your non-freesat list. There may be other KU band channels in the mix from 19.2E. It also seems that the channel scan included encrypted content which you can't watch at all.
The channel numbers are created in the order they happen to be added (and can be changed)
You now have a single dish on 28.2/28.5E so of course none of the 19.5E will work (and in any case the RTE ones aren't usable in the UK).
Any of these channels should be usable in non freesat mode.
http://en.kingofsat.net/freqs.php?&pos=28.2E&standard=All&ordre=freq&filtre=Clear
I would make a note of your recording schedule and do a factory reset. Then do a full manual tune for fta channels only.
Tv3 isn't on Saorsat so I'd imagine the channels are just there from a general scan of 28 that included the encrypted channels.