What goes wrong
Reorder grey, and the size.
Packaging Suppliers lists Mailing bags for this line. They are also called shoe bags. The category says they are European made from recycled film and 100% recyclable, and opaque so the contents are not visible.
The check before you reorder
Choose the mailer that fits the goods. A much larger bag folds and looks like a different pack.
Keep each size in its own shelf slot.
Dispatch on that order
A Friday order on Packaging Suppliers that includes Mailing bags aims for Monday. A bank holiday on Friday or Monday moves that delivery. The 3pm cutoff is still the same-day dispatch rule.