They won’t do anything. They post a warning before you submit to double check and ensure everything is correct. Your emails will go to the specific embassy but the website and cancellation will come from MoFA. Those who you talk to literally have no power to change anything.
Anonymous participant - ok, since you said you are “considering” changing nationalities and you say the paperwork takes years, maybe your DTV will be expired by the time you are able to change nationalities. I assumed you were much farther along in my first message.