Noticed when testing T6519 on Windows:
Giving a date higher than 19.01.2038 and lower than 06.02.2106 on key generation in Kleopatra results in a "General Error":
On the command line the error message is "Invalid value".
C:\Users\g10code.WIN-TEST3\Documents>gpg -v --quick-gen-key abc default default 2038-01-20 [...] gpg: Schlüsselerzeugung fehlgeschlagen: Ungültiger Wert [...]