When the offset target date falls outside the current two-month view, flip .prev months (1 month/step) until the target day cell enters month1 view, instead of silently falling back to today. JS-dispatched clicks avoid the .date-range-length-tip hover interception.
Also switch the expected (#beginDate) day-cell click to _dom_click (matching actual #daterange): the range-length tooltip intercepts the second click on non-today cells during single-day range selection, causing timeouts.
Verified end-to-end: offset=45 (-> 2026-06-14, cross-month) expected task succeeded and downloaded 6-14 data without fallback.
Co-Authored-By: Claude <noreply@anthropic.com>
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