eBay
Multi-quantity eBay orders and partial dispatch
Single-item orders are the case every workflow is built for. Multi-quantity orders are the case that exposes whether the workflow was built properly.
What actually happens
A buyer orders three of something. Your supplier ships two now and one next week, or ships all three in separate parcels because that is how their warehouse works.
You now have one eBay order and up to three tracking numbers, and one field to put them in if your sheet is organised by order.
The sheet is the constraint
If your spreadsheet has one row per order, a partial dispatch has nowhere to go. Sellers respond by picking one tracking number and putting it in, which means the other parcels are invisible to everyone including the buyer.
One row per fulfilment unit looks wasteful on single-item orders and is the only layout that represents reality on multi-item ones.
Uploading against the right unit
eBay supports shipping part of an order, but the upload has to identify which part. A tracking number attached to the whole order when only part of it shipped means the rest looks dispatched when it is not - and that misrepresentation is worse than the delay it was hiding.
The buyer experience
Buyers do not expect split parcels and do not read notifications carefully. They receive two of three items, see one tracking number showing delivered, and conclude something is missing.
One message at dispatch - this is coming in two parcels, here are both numbers, the second is a few days behind - prevents nearly all of it.
Pricing multi-quantity sales
If your supplier charges per-unit shipping, a three-unit order costs three times the shipping, and if your listing offered a combined rate your margin on that sale is worse than you modelled.
Check the multi-unit economics on anything where quantity sales are common. It is a routine place to be quietly unprofitable.
The deadline applies per line
Each unit carries the same dispatch expectation. A fast supplier on two units and a slow one on the third means part of the order is at risk while the order-level view looks fine.
This is the same argument as everywhere else in this series: track the unit, not the order, because the unit is what actually ships.