Banding follows the upper bound
A channel is placed in a band by the slowest delivery it stands behind, never its fastest. A channel measuring 5–12 days is banded 8–12 — the fast deliveries beat the promise instead of the slow ones breaking it.
Guide · Transit bands
Why we promise 8–12 days instead of 5
A transit band is the delivery promise WooliiPorter actually sells: a destination country times a working-day range, such as 8–12 days, in place of a single day-count. Channels are assigned to bands by their upper bound — the slowest delivery they stand behind — and the band you choose at order time is frozen on the parcel.
Most China shipping is quoted as one number — “5 days” — with the conditions that make it false left unstated. This page is the methodology behind the alternative: how bands are built, why they are conservative, and what keeps them honest after you have paid.
A single day-count is a marketing number
Cross-border transit is a distribution, not a point. Customs inspects some parcels and waves others through; linehaul departures cluster and gap; weekends and destination holidays sit wherever they fall. A channel that usually delivers in 5 working days and sometimes takes 11 is not a 5-day channel — quoting the 5 makes every slower delivery a broken promise the merchant absorbs in support tickets and refund requests. WooliiPorter’s position is mechanical: a delivery promise must state the range it is actually kept within, or it is not a promise — it is an advertisement wearing one’s clothes.
Banding by the upper bound: a worked example
Bands are assigned conservatively. Here is the rule applied to a real case on the Great Britain lane:
| Step | Range | Why |
|---|---|---|
| What the channel measures on the lane | 5–12 working days | Real deliveries land across the whole range — the fast end exists, but so does the slow end. |
| The tempting band | 5–8 days | Sells better, and is broken by every delivery that takes 9 or more days. The channel’s own record contradicts the promise. |
| The band it actually gets | 8–12 days | The upper bound is inside the promise. Deliveries at the fast end arrive early against it; deliveries at the slow end still keep it. |
The asymmetry is the point. Banding by the fast end converts the channel’s ordinary slow deliveries into failures; banding by the slow end converts its ordinary fast deliveries into early arrivals. Only one of those is a promise a network can sign its name to.
The four rules that make a band a promise
The promise freezes on the parcel
The band you chose at order time is recorded on the parcel itself. If the lane is re-banded, re-priced or re-routed tomorrow, your parcel’s promise does not move — changes apply to future orders, never to commitments already made.
Empty bands are not offered
If no channel on a lane currently qualifies for a band, that band does not appear for that lane. You cannot buy a promise the network has no way to keep — an absent option is honest; an aspirational one is not.
Attainment is measured, and slipping channels are demoted
Delivered parcels are checked against the band they were sold under, continuously. A channel whose measured attainment slips is demoted in routing — and if it no longer supports its band’s upper bound, it drops out of the band rather than dragging the promise down with it.
What the band changes for routing
The band is the second of the three routing layers: after the compliance gate eliminates the channels that cannot carry a parcel at all, the band eliminates the ones that cannot keep its promise, and cost chooses among the rest. Because the promise is frozen on the parcel, the routing engine is always honoring a recorded commitment rather than optimizing against a moving target. The full decision, including the fail-closed rules and the per-parcel decision record, is in the multi-carrier routing guide.
What is deliberately not claimed
WooliiPorter publishes no aggregate on-time percentage, and the worked example above is an illustration of the banding rule, not a quote for a specific lane. Attainment figures are measured per channel per lane and drive routing internally; the bands a lane offers today, with prices, come from the live rate table at booking time.
Common questions
Why does WooliiPorter promise 8–12 days instead of 5?
Because an unconditional single day-count cannot be honored on a real cross-border lane. Customs inspection, linehaul variance and weekends produce a distribution of outcomes, not a point — so a promise that can be kept has to name the range. A channel measuring 5–12 working days is sold as 8–12: the fast deliveries arrive early against the promise instead of the slow ones breaking it.
What exactly is a transit band?
The product WooliiPorter sells on a lane: a destination country times a working-day range, such as 8–12 days. It replaces per-carrier service names — you choose the promise, and the routing engine chooses, per parcel, which compliant channel inside that band carries it.
What happens to my promise after I order?
It freezes on the parcel. The band chosen at order time is recorded on the shipment itself, so later re-banding, re-pricing or routing changes never rewrite it. Tracking and the order timeline report against the promise you bought, not against whatever the lane offers today.
Why do some lanes show fewer bands than others?
Because a band is only offered where a qualifying channel currently exists. A lane with no channel that supports a faster band simply does not show that band — the network does not display a promise it cannot keep and then apologize per parcel.
How do the bands stay honest over time?
By measurement rather than declaration. Every delivered parcel is scored against the band it was sold under; channels whose measured attainment slips are demoted in routing, and a channel that stops supporting its band’s upper bound leaves the band. The published range therefore tracks what the network is currently delivering, not what a rate card once said.