In fact every bond film premiered on itv including OHMSS which premiered in September 1978. As far as I remember bbc1 have shown the unofficial film never say never again but that too premiered originally on itv. They did have a one off screening of from Russia with love on bbc2 about four years ago as part of some season.
If they do go back on itv I can see them making a big deal of it. Bond is back where he belongs or something like that!
You are correct. The BBC have never shown On Her Majesty's Secret Service
. The only official Bond film they have shown is From Russia With Love
as a special one-off. The execrable, unoffical Never Say Never Again
doesn't count, of course.