[Spencer]

Itv one on 103 prior to 15 Nov 2001 was indeed an RPG data insert on a dummy channel on 11778V that never had any video or audio present.

It disappeared from the EPG when the first 16 itv regions launched simultaneously to the EPG at 1700 that day, despite having been on air since 5 November 2001.

The method has not been used since on any service. These days the channels are just launched on a number inserted as new, changed, or removed straight away 

They stay on air fir around 30 minutes after EPG updates, before getting switched off.

The difference here is that 101-105 have to be listed on the EPG, as required by Ofcom:

EPG providers must ensure that the five national general entertainment PSB channels (BBC1, BBC2, Channel 3 services, Channel 4 and Channel 5) are listed in the first 5 slots of the EPG.

Source: Source: www.ofcom.org.uk