The difficulty comes from the As character anchor of the outer frame. But let’s take things in order.
Caption creates a frame around the images. This outer frames takes anchoring and type properties from the image, i.e. it is anchored As character so that there is no change in formatting. Inside the frame, the image becomes anchored to the caption paragraph in To paragraph mode.
This would suggest that playing with Position properties in
Type could move the image below the paragraph caption. Indeed it does, but there is no way to set wrapping so that it does not interfere with text surrounding the outer frame. This is probably because wrapping in taken into account only within the outer frame. Since the outer frame is As character, it behaves like a huge character. I bet that for simplicity the layout engine considers only the (outer) frame rectangle to compute text flow, ignoring out of frame elements (which logically makes sense) unless Allow overlap is unchecked.
To avoid this, I usually anchor my images To Paragraph (unless there is a good reason to consider them as big characters, in which case I have no caption).
While experimenting, I could not find a way to shift the caption through style modification. Every attempt resulted in the situation becoming worse and worse.
I am afraid that you can’t but reinsert your image and selecting
Caption with Position
Start instead of
End. To avoid future issues, take care to anchor your images To paragraph. This will make your images more independent from the text and will allow to position them easily through styles.
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