Hello Lynn,
From my perspective this 'externalReference' pattern introduced in ServiceOrder API should be propagated in next ProductOrder API release.
This feature allows you to store several external.id for a given order but also provide an information about the id 'owner' . It could be useful if you have to track some legacy order identifier (you track both the id but also the app provided it) but also in B2B2B where we would like to track 2 external id for a given order.
BTW, probably the addition of jeopardy, error message and milestone introduced for serviceOrder could also make sense for productOrder.
Hope it helps,
Ludovic
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Ludovic Robert
Orange
My answer are my own & don't represent necessarily my company or the TMF
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