Actually, the networks started using videotape around 1957, but it was primarily for variety shows, game-shows, and daytime fare, as I’m sure you know. Unusual for tape to be used for a nighttime network show back then, though. The funny thing is that they also made kinescopes from tape too. When those ‘taped’ “Zone” episodes used to be shown in syndication over thirty-years ago, they were actually ‘film’ prints of the taped show.
Wasn’t Raoul Dahl’s show “Way Out” (which was in the TZ vein, from around 1961) shot on tape? There was another short summer series from the same era, “Great Ghost Stories,” but I think it was broadcast live. Maybe. Not 100% sure.
They would reuse and reuse kinescopes until they wore out, which is why, sadly, most of very early T.V. shows are now only seen in one'/s own memory.
I know that some KUKLA, FRAN, and OLLIE were preserved, but that show was on for decades.