Decide on rehearsal packaging and merging

Rehearsal packaging answers a question you cannot answer from a listing: what will this basket weigh and measure once it is actually packed, and will the volume decide the charge?

Merging is the same question at a larger scale. Both are worth doing when they change the billing basis, and a waste of a handling day when they do not.

Justification for a rehearsal comes from uncertainty about the billing basis, not from the size of the parcel. The test is whether the packed dimensions could plausibly cross the point at which volumetric weight exceeds the actual weight; if both divisors already return a figure below the scale weight, a rehearsal only confirms what is known. A merge follows the same logic: it earns its fee when it removes a minimum charge or a duplicated handling step, not when it moves several small parcels into one that is billed on volume. A rehearsal is information, and information earns its cost only when it changes the decision at hand.

Chargeable weight is calculated rather than observed. Volumetric weight follows length by width by height, divided by the divisor the line applies and multiplied by 1000, with 5000 and 6000 grams per litre the two divisors in common use. The choice is not cosmetic: a parcel measuring 50 by 40 by 30 centimetres yields 12 kg at a divisor of 5000 and 10 kg at 6000, a difference of two kilograms on an identical box. Which divisor applies is a property of the line and should be confirmed rather than simply assumed. The same box can therefore be priced on two different weights without any physical difference between the two.

Merging two light parcels into one that crosses onto volumetric billing is the classic form of this error, and it is expensive because the fee is paid before the consequence appears. The parcel is heavier on paper than on the scale, and the difference is charged on every subsequent leg of the route. Recording a rehearsal weight and then ignoring it is the quieter failure: the information was purchased, and the following order still begins at the same estimate. Neither error appears on an invoice as a mistake, which is what makes both persistent. The fee is charged either way, which makes the mistake hard to see afterwards at all.

Step 7 hands step 8 a chargeable weight and a contents list. The weight is the only figure on which line rates can be compared honestly, since quoting two lines at different assumed weights is not a comparison at all. The contents list matters separately, because line acceptance is decided by category rather than by mass. Where a rehearsal was skipped deliberately, that decision should be recorded as a decision; an unrecorded assumption becomes an unexplained discrepancy at dispatch, and recording it costs a line while preventing an argument. The next step can compare only the figures that this one hands over in writing, at the exact weight actually recorded.