Turns out you will get the variations using the API call above if you first save content for the variation through the UI. But to save content into a variation through the API you need the variation id which isnt possible if the id of the default variation isnt returned initially.
My current workaround: create a new variation right away; in the UI this seems to show up as the only default variation. This indicates to me that the "default" variation you see in the UI isnt existing untill you actually press save. At that moment its probably created which explains why it wont show up in the GET variation calls right after article creation.
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Richard Kiewiet
Product Owner
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