The truck cannot make Thursday's window. The co-op still has you on the board. Your assistant wrote an apology with a story about the weather. The dock does not need the weather. It needs a new window or a cancel.
A delivery change is a decision with a clock. Write it so the person who prints the receiving list can file it.
One drop, old window, new window
Name the decision. "I need you to accept Friday 6–8 in place of Thursday 6–8 for drop 14, offer Saturday morning, or cancel Thursday's drop." Give the product and quantity as they print them, the PO or drop name they already use, and what you will do if they cancel — hold the lot, or send it elsewhere.
Do not attach the order sheet. RelayLink does not carry attachments. Describe the order in the briefing. Sheets stay on the channel you already use.
One drop per message. A week of routing is a call.
Write for the office, not the person you last saw at the dock
Assume a colleague opens this. Use their words for the bay and the drop. You assumed the cooler still has space on Friday. You assumed the same SKU is still on the order. You assumed they can refuse a partial. Label those.
A nickname you use for the buyer stays on your side. The package uses the names they print.
The reply is the point. A voicemail they might hear after the truck has left is not a plan.
You approve it; they reply from the office inbox
You review the wording. They do not need an account. Most co-op addresses will never activate RelayLink. The briefing arrives as email. They can reply there. If that address already has an activated account, you need an accepted pair for a new thread.
Give the time the truck actually needs an answer, and say what you will do if you do not hear — roll, cancel, or call the dock. Honour it. A decorative time is how you become the farm they cannot schedule.
If a second person must see it — the buyer and receiving — one briefing still goes to one mailbox. Say who else has to know before you roll.
After they answer
Write back the window in their words, and ask them to correct that sentence. Then move the truck. Do not leave Thursday on your own board "just in case." Two windows for one lot is how a dock waits and a cooler turns.
The season can still be messy. This email is the drop they will staff.