If your produce, seafood and meat suppliers are on weekly payment, you’re a low-priority customer to renegotiate but a high-priority customer to keep. The asymmetry works in your favour.
The single-email ask
Hi, we’re doing a cashflow tidy and want to move all supplier accounts onto net-21 from the [date]. Happy to set up direct debit. Let me know if there’s anything I need to confirm.
9 out of 10 suppliers will say yes. The 10th will say net-14 — take it. You’ve just freed up 14 days of working capital that was sitting in the next week’s payment run.