Trial pad drawing is identified. Required destination and sample condition are in the confirmation. I've sent those beside delivered-pad photographs.

Ask for the supplied pad identity and a comparison through contact, hold and release. Keep availability of the agreed pads as a separate option rather than assuming the substitute must be accepted.

Has the seller acknowledged the substitution itself, or are they still disputing what was delivered?

Substitution acknowledged. They sent its drawing but no sample comparison. Asked whether the agreed pads can be supplied instead.

Who reviews the changed contact geometry with the sample-condition requirement, rather than letting the new drawing count as acceptance by itself?

And keep the installation hold with that owner. A drawing arriving can look like the missing approval to someone arranging the fitter's visit.

Tooling and quality own review. Seller offers the agreed pads, date unconfirmed; no substitute accepted and nothing fitted.

Does the offer identify the same drawing revision as the trial? That is the next supply detail to settle.