Render a register date as ISO-8601, the way --iso-dates prints it. The register is a
German one, so:
a date-only value — the register sends those as UTC midnight (InbetriebnahmeDatum,
EinheitRegistrierungsdatum, …) — becomes the calendar date, YYYY-MM-DD;
an instant (DatumLetzteAktualisierung) becomes German local time with an explicit
offset, 2020-02-20T17:28:35.250+01:00 (+02:00 in summer time); the milliseconds are
shown only when they aren't zero. It is the same instant as the UTC form, written for a
German reader.
A year outside 1–9999, or an offset that isn't whole minutes (Berlin's local mean time
before 1893), falls back to Date.toISOString() (UTC, Z).
Render a register date as ISO-8601, the way
--iso-datesprints it. The register is a German one, so:InbetriebnahmeDatum,EinheitRegistrierungsdatum, …) — becomes the calendar date,YYYY-MM-DD;DatumLetzteAktualisierung) becomes German local time with an explicit offset,2020-02-20T17:28:35.250+01:00(+02:00in summer time); the milliseconds are shown only when they aren't zero. It is the same instant as the UTC form, written for a German reader. A year outside 1–9999, or an offset that isn't whole minutes (Berlin's local mean time before 1893), falls back toDate.toISOString()(UTC,Z).