[WillPS]

When you say non-EPG, do you mean those placeholders when a channel closes another takes their place and the like?

All my boxes and TVs seem to have done that over the years. The same with duplicate channels.

Way back in pre-Freeview days, when channels were first added to multiplexes they sometimes wouldn't have a channel number assigned and they'd end up on 80x, I remember this was where CBBC/Cbeebies first appeared and also where the BBCi/red button feeds appeared until they were moved to 30x for the world cup proper.

Later on I had a Philips DTT box (not ONdigital) and if you did a scan on a good day it'd park the ITV1 Yorkshire feed up in 80x (this was before boxes used to ask which region you lived in or for a postcode or anything like that, so I presume it awarded EPG number to whichever channel presented with the best signal strength?). I always presumed S4C/C4 would appear in that range but I can't confirm it ever worked that way for DVB-T2.