Is the issue of the Erased the issue of residency or of citizenship?

The basic problem of the issue of the Erased is the removal from the registry of permanent residents of Slovenia. Because they have not decided for the citizenship or because they were unlawfully prevented from submitting the application or because the submitted application was denied (upon dissolution of SFRY, citizens of other republics of the former SFRY also had the right to apply for citizenship of Slovenia) they unlawfully lost their status as permanent residents of Slovenia which they previously already had.