It is consistently being missed that, if Cardinal Ratzinger dies before Francis, thereby transforming the Benny’s into sedes, that state of affairs does not come to an end for them upon the subsequent/eventual death of Francis:
Since they believe him to be an antipope, and this alleged antipope has appointed many of the Cardinal-electors eligible to vote in the next conclave, they must hold that next conclave invalid.
Consequently, they are locked into sedevacantism in perpetuity, with every future conclave being invalid, and the possibility of restoring the papacy closed.
Their only escape is to humbly acknowledge that, whatever irregularities may have existed in the resignation of BXVI, Francis is pope.