This issue is about the wording in 20.397 style:vertical-pos and 20.398 style:vertical-rel, ODF 1.3 part 3. It is not clear to which elements these attributes can be applied and which restrictions exists.

Current text is:
The style:vertical-pos attribute specifies the vertical alignment of a frame relative to a specific area.
The style:vertical-rel attribute specifies the area against which the vertical position of a frame is positioned.

Problems:

(A) Is 'frame' a <draw:frame> element? Then that should have been written as reference to that element. But at least LibreOffice uses it for all kind of shapes.
(B) The schema allows it in element 17.21 <style:graphic-properties> and in element 17.19 <style:list-level-properties>.

(c) The "Table 23 - Vertical Relation Values" lists the restriction of the values by anchor-type. It is not clear, whether the use in lists has restrictions of the values too.

A solution needs to be discussed.
To reduce complexity, I can image to divide the text into a section for use with <style:list-level-properties> and a second section for use with <style:graphic-properties>.
To cover not only <draw:frame> but other shapes too, it might be necessary to define a technical term "graphical element" or "graphical object" or "drawing shape".