GET /v1/org/fulfilment/imports/{importId}Imports run on a queue, so a push typically finishes within a couple of minutes. Poll
every 30 seconds or so — a tight loop only spends your rate limit.
Status values
Counts
completed with failures is the normal case: valid activities are never held back
because others were wrong.
Counts settle when the import reaches completed, failed or cancelled. While it is
still processing, failed reads 0 and processed is the running total.
errorReportUrl is a signed link to the same rejections as a spreadsheet. It is null
until the import finishes and stays null when nothing was rejected.

