What is your source of this change?
If the source is "SDFI Luftbilder" then it is not true that you can see these lines.

If you are not able to see the physical structure in the area, then your mappings are fictive. As I can see you must put this into openhistorymap.org and leave openstreetmap to the current view on ground.

From the https://wiki.openstreetmap.org/wiki/Tag:railway=abandoned 
"A tag to map former railways, where the rails have been removed but the route is still visible with ties/sleepers, signals or other railroad right of way signs or infrastructure."
As you can see it is only when there is a physical sign of the structure, not if it has been totally removed and changed to eg. a field or a building.

Good readings:

https://wiki.openstreetmap.org/wiki/Ground_truth

https://wiki.openstreetmap.org/wiki/Good_practice#Map_what's_on_the_ground

And specially this 
https://wiki.openstreetmap.org/wiki/Good_practice#Don't_map_historic_events_and_historic_features
