Why ship to site is not utilised when using a tax rate rule - bill to site applies only

Summary: When using a tax rate rule with ship to / ship from criteria, the tax classification code I would like applied to a transaction has to be set at bill to site, rather than the ship to site it applies to, to ensure it appears on the AR invoice. Can anyone explain how to make it apply from ship to site please ?

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Version (include the version you are using, if applicable): Oracle Fusion Cloud 23B

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