The Four Doctor wrote:
The prints are most likely "bicycled" prints ex-ABC or NZBC which means they will have been cut to ribbons by the ultra-conservative censors of 1960s Australasia.
Remember that as late as The Sun Makers, the Australian censors cut the line "stuff the Company!" as they wanted to remind children to respect any authority.
Strangely enough, many of those censored clips were actually preserved, even though the prints were junked. Many of them are on Lost in Time.