When the monthly report stops being a scramble.

The clearest sign is that you re-format the file from scratch every cycle. A new column appears, or two rows fold into one, or your finance lead has to 'translate' the export before handing it over. If you can't point at a canonical key that survives from month to month, the work is still ad-hoc no matter how often the report runs. The second sign is the same question being asked three weeks later — could you re-run that for the last six months? If the answer is to rebuild the file, the format isn't settled, and no recursive report will hold together for longer than a quarter.

Recurring runs on a fixed cadence held to the day. The format freezes — same canonical keys, same column order, same convention — so the deliverable looks the same next month as it did last month. The operator stops reading the raw feed and starts handing back a clean summary, usually a short email or a single sheet, with the variation flagged and explained. Once the cadence is held, scope creep gets contained: changes count as a new conversation and a new row, not a free addition to last month's deliverable.

Pick one stable source-of-truth file and lock the format for at least two consecutive cycles before you call it recurring. Write down the canonical keys and the conversion rules at the top of the deliverable. Send a short summary email instead of a working file, so the hand-off stays small and the deliverable doesn't drift. The line between ad-hoc and recurring is mostly discipline, not technology — you stop staying late on the report, and once you stop, you notice how much of the cleanup was recreating the same shape every month.