Complex sentence: The final is also broadcast on radio initially on BBC Light Programme until the 1967 contest when from 1968 it was broadcast on BBC Radio 1 the contest was then broadcast on BBC Radio 2 from the 1974 contest where it has remained ever since.
Split into simpler sentences: The final is also broadcast on radio, initially on BBC Light Programme until the 1967 contest. From 1968 it was broadcast on BBC Radio 1, moving to to BBC Radio 2 from the 1974 contest where it has remained ever since.