For the small appendix in the N-W i will pass end off this week to double check, it was added by same changeset and follow the cadastral  parcel, but a cadastral parcel give you ownership not fuction , if you take the https://www.openstreetmap.org/way/227645310 there is also a part on the back "594M2" but it's in use by the municipality not the fire station.

Let's keep this note open until i will go to doublecheck.