But if I don't get wrong, Sky Movies Premier Widescreen (closed down in 2003) was a channel with a separate schedule, right?
Sky Cinema Italia went into a similar WS switch process but much later, with Sky Cinema 16:9, with a separate schedule (launched in 2003, along with Sky and the other Sky Cinema channels; note that its predecessor, Tele+, had a Tele+ 16:9 channel too.. Canal+ Spain, France, Poland and a couple of others had similar equivalents too) becoming a new channel, Sky Cinema Hits, and obviously all the remaining Sky Cinema's switching to WS
By the way, in a market such as the British one with the BBC channels switching to WS in 1998 already, one would have expected the Sky channels to have gone WS much earlier than 2003