Daylight-saving gaps: local times that never occurred
Why software must reject or explicitly repair a wall-clock time skipped by a forward clock transition.
Calculation contract · released 2026-08-18
Definition
A gap is a forward offset transition that leaves a range of local clock labels with no corresponding UTC instant.
Calculation procedure
Validate the local timestamp against the pinned timezone rules. If it falls in a gap, reject it or retain a documented correction supplied by the record owner; never normalize it silently.
Required inputs
- Local civil timestamp
- IANA timezone
- Pinned tzdb release
- Correction evidence if the source time is invalid
Maha convention
Maha distinguishes invalid local input from a valid instant near the transition and records any user-authorized correction as provenance.
Uncertainty and edge cases
Automatically shifting a gap time forward can create a plausible but unsupported chart, especially for time-sensitive angles.
What this does not establish
A software-repaired timestamp is not an observed event time.
Authoritative references
These sources establish the calculation vocabulary, data product, or transformation convention. They do not establish astrological interpretation.
- Time Zone Database
Internet Assigned Numbers Authority · 2026c
Versioned civil-time-zone identifiers, UTC offsets, daylight-saving transitions, and historical rules for representative locations.
Boundary: The database records civil-time practice and can contain historical uncertainty; it does not supply leap seconds or astronomical time scales.