Hello,
according to this current photo
https://www.mapillary.com/app/?pKey=3305608249589956&focus=photo&lat=51.268712793333&lng=6.7484750024&z=17 there is no speed limit 30 km/h. Even if there was a speed limit from 07:00 to 17:00, a simple maxspeed=30 would be wrong. In cases like this, please use maxspeed:conditional (https://wiki.openstreetmap.org/wiki/Key:maxspeed:conditional).
I reverted your changes.
Best regards