next_expected_at is the next data point
What's new
next_expected_at in the API catalog is now the time the next new data point is expected for the series at its canonical resolution. Before, it was the time of the next scheduled refresh attempt, which could fall on a day that publishes nothing new.
The Next time in the chart snapshot follows the same rule for the resolution you select. The Updated time is when new data last arrived for that resolution.
Methodology
A series that gains a point when a fixed bucket closes, such as a live price interval or a 12-hour derivatives series, reports the close of the current bucket. Its update_frequency now reflects that bucket.
Weekday series skip weekends and US market holidays. next_expected_at is an estimate, not a promise of publication.