[IDML] Positions on baseline grid

I've got TextFrames located in a group. This group is located in a page.

My TextFrames shapes are rectangular and there is no rotation.

I also have a baseline grid defined on my page.

Properties for my Grid :

HorizontalGridlineDivision="958.1102362204724" VerticalGridlineDivision="26.25" HorizontalGridSubdivision="2" VerticalGridSubdivision="1" BaselineGridShown="true" BaselineStart="3.350551181102362" BaselineDivision="5.2"

Here is an example of TextFrame position relative to my group baseline :

<PathPointArray>

<PathPointType Anchor="-196.46828263062793 -22.427716535432864" LeftDirection="-196.46828263062793 -22.427716535432864" RightDirection="-196.46828263062793 -22.427716535432864"/>

<PathPointType Anchor="-196.46828263062793 -11.905511811023532" LeftDirection="-196.46828263062793 -11.905511811023532" RightDirection="-196.46828263062793 -11.905511811023532"/>

<PathPointType Anchor="-17.604668166479218 -11.905511811023532" LeftDirection="-17.604668166479218 -11.905511811023532" RightDirection="-17.604668166479218 -11.905511811023532"/>

<PathPointType Anchor="-17.604668166479218 -22.427716535432864" LeftDirection="-17.604668166479218 -22.427716535432864" RightDirection="-17.604668166479218 -22.427716535432864"/>

</PathPointArray>

Ideally I would like to know my TextFrame position on the baseline grid on my page.

Otherwise is there a method to calculate TextFrame coordinates into my page ? (and not into my group)

Thanks.