Hi, before changing the road category, did you familiarize yourself with the rules for mapping roads in Poland? The wiki is in Polish, so you may have difficulty understanding the full content of the descriptions. One of them says that: the official road classification may be auxiliary, but not decisive when determining the value of the 'highway=*' tag

The roads you changed should definitely not have the highway=tertiary category. The edit will be reverted unless you have arguments to raise the category of these roads.

https://wiki.openstreetmap.org/wiki/Drogi#Klasyfikacja_urzędowa_a_oznaczenia_na_OpenStreetMap
https://wiki.openstreetmap.org/wiki/Pl:Znakowanie_dróg_w_Polsce