It's a forever loan for whatever your average payables total to over 90 days (so $10k every month would be a $30k loan). The loan lasts forever or until you close out that line of credit/wind up the company.
The loan lasts as long as your payables continue to average above $10k/month (or 30k in every rolling 3mo period). Businesses get into trouble when they have a short term disruption and suddenly their cash flow is impacted, then they have no more receivables and have to quickly come up with money to close out the payables. If they are already over leveraged or don't have creditworthiness then they can become insolvent.
