check-digit or sonderzeichen

Though the mandate was delayed and not without controversy, reforms to standardise the naming-convention for bank accounts, to make the IBAN (International Bank Account Number) coding sequence also apply to domestic transactions—the changes incorporated for what is called the Single Euro Payments Area (SEPA), came across pretty seamlessly. Compliance helps eliminate the potential for dysglossia or duplication during transcription.
I noticed, however, that in practise, it yielded another affront against the maligned Umlaut. I enjoy completing payments with the automated tellers as it is one of the rare chances for me to use a German keyboard layout and try to use the language properly. Due to SEPA parameters, though, what are considered special characters are culled. It's like the initiative in the UK to remove all punctuation marks from street names so as to ensure that they are not garbled in navigation devices. “Turn left at St#àààààààà John█qwkl Wood.” I am surprised that the ü and ö are still accommodated on German vehicle license plates, as lands that employ Cyrillic (or Greek) characters are hardly afforded the same: only Latin appearing letters are allowed (though the H is really an E) and one will never see a backwards R, Space-Invader combination on a Bulgarian plated car. Space and data is not really a premium any longer and one has to wonder about the enforcement of old call-signs and the frailties of computing platforms, like the wondrous but technical legacy of British zip-codes—and registration plates.  I wonder how this policing might change in the future, now that the US has relinquished its hold on the Internet Corporation for Assigned Names and Numbers (ICANN) and now the world at large can fix standards.