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I hold a combination of the views, that during the reign of a Pope, Christ supplies jurisdiction through the Pope to the bishops, but during an interregnum He supplies it directly to the bishops ... respecting the designations for authority put in place by the previous pope.  If a bishop were to pass away and another one step in his place during a lengthy interregum, I hold that Our Lord would invest him with the necessary jurisdiction on the basis of an epikeiea.  In the early Church, it happened regularly that the people of a "diocese" (or the equivalent) would designate or elect their bishop, and then bishops from neighboring cities would come to consecrate the individual ... with very little involvement from the Bishop of Rome.  That does not mean that even in those situations the jurisdiction itself did not come from Rome, at least through a tacit delegation, but nevertheless there's a distinction between the designation and election of a pope and the formal supplying of jurisdiction.  That's why in a scenario where, say, the Vatican were nuked and all the Cardinials killed, the Church could find any means necessary to designate the man they wanted to become Pope, and the power itself would be formally invested in him by God.  Election (or designation for office) can happen in a variety of ways, but only God formally invests the designee with authority (unlike with any other office in the Church).