[tz] Japanese Summer time fallback transition in autumn 2020?

One other thing. The Japanese government is considering adopting daylight saving time for the 2020 Tokyo Olympics. Will this issue about 25-hour (or 26-hour) days come up in 2020? For example, could there be a 26-hour day in September 2020 with times ranging from 00:00 to 26:00? If so, a *lot* of computers will have to be reprogrammed, as no software I'm aware of supports timestamps like that now.