Yes Rosey04, it is definitely Sunday.
I believe the thinking behind it was that we would be able to make more of the time we have in the build-up to the switch-on rather than have it all crammed into a frenetic couple of hours. Hopefully shops will be open and doing their bit to join in the fun too. With regard to exact time of the switch-on, and whats on during the day, that will be announced by the committee. I don't know any more than that at this time.