Interactive publication
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Spring-forward gap (nonexistent local time)
When clocks jump forward, a local wall time never occurs (e.g. 02:30 on 2026-03-08 in America/New_York). Resolving it to a slot requires a declared policy, not a silent guess.
Class
Case to account for
Affects
3 conversions
01
Detection
The zone resolves the requested wall time to a different clock time (it was skipped).
02
Mitigation
01
Declare a policy: shift-forward (post-gap instant), shift-back, or reject.
02
Record wasNonexistent on the result (requested vs executed).
03
Affected conversions
Timestamp + zonehour-of-week slot
OPENBroadcast day (declared cutover) ⇄ slot-set
OPENDaypart (local band) ⇄ UTC slot-set
OPEN