Thank you for the update to zone Europe/Budapest.
Geza Nyary is another developer of astrology software who did careful local research and shared it with the TZ community.

In my database of birth data records, there were 99'800 born in Hungary.
259 of these records were affected by the correction.

count  year
    12 1919
    34 1920
     1 1945
   206 1950
     1 1955
     1 1980
     1 1981
     1 1982
     1 1983

Thanks for those corrections. I installed the attached patch to the development
database on GitHub. It's not exactly what you emailed me, but it should generate
equivalent transitions.

It'd help if we could list citations for the transitions; are URLs available for
each decree etc. that you consulted? We could add them as comments.

Thanks again.