Incorrect/redundant Dutch translations in locale file

[lucasmoeskops]

Wagtailstreamforms provides some translations for strings that are already provided by Django. I wonder why this is necessary. The problem is that these translations are different for the Dutch locale. E.g. months are translated with capital letters instead of all lowercase. Also there are some translation errors (only checked the Dutch locale), e.g. January is translated as January instead of januari.

Is there a reason to keep these translations, or should the translations that are already available in the django default locale be removed?