Not sure of frequency but it was broadcasting football the other day on Channel 136 (men and Motors). probably use this until the full channel is ready to launch and then become channel 120 so that ITV 2,3 and 4 are all next to each other.
Sky viewers will still be able to view ITV4 by adding the channel manually. To do so, press services, then 4 (system setup) and 4 (add channels). Enter the frequency 10.758, a polarisation of V, a symbol rate of 22.0 (use the left/right arrow buttons) and an FEC of 5/6, then select 'Find channels'. From the list that appears, select 10072 and press the yellow button, then select to store. The channel will now be accessible via services, then the 'Other Channels' menu.
10.758 v 22.0 5/6 search and yellow dot the ch 10072 and it'll be in the "other channels bit in services