The administrator remains in charge until a new bishop or archbishop is installed into office ending the sede vacante period or until he presents his resignation to the college of consultors.
Since the Investiture Controversy in 11th and 12th centuries the cathedral chapters used to elect the Catholic bishops in the Holy Roman Empire.
Candidates elected, who lacked canon law prerequisites and/or papal confirmation, would officially only hold the title diocesan/archdiocesan administrator (but nevertheless colloquially be referred to as prince-bishop).
However, in the early years of Reformation, with the schism not yet fully implemented, it was not always obvious, who tended to Protestantism, so that some candidates only turned out to be Protestants after they had been papally confirmed as bishop and imperially invested as prince.
Many Protestant candidates, elected by the capitulars, neither achieved papal confirmation nor a liege indult, but nevertheless, as a matter of fact held de facto princely power.
The information that Protestant clerical rulers would generally have been called administrators, as written in several encyclopedias, does not fit historically documented practice.
However, one common restriction was that administered prince-bishoprics were denied to emit their deputies to the diets of the Empire or of the imperial circles (German: Reichstag, or Kreistag, respectively).