Why an import sometimes waits

Imports have their own AI allowance, 3× the assistant's. At the per-minute limit an import waits a few seconds, then carries on.

1. Reading a workbook takes one AI request per tab, plus one to sort the tabs.
2. Imports have their own allowance, so they never use up the assistant's messages.
3. At the per-minute limit, the import tells you the limit, waits and carries on by itself.
4. If the day's import allowance is used up, the tab says so. Try again tomorrow.
5. AI Usage shows how much of the import allowance is left.