hi! other responses are welcome, but you may be interested in these related posts

• Did Hitler designate a successor in the event he was killed? Was there a formal procedure laid out in case succession was necessary?

• Did Hitler ever give any thought to choosing a successor?

• How close was Albert Speer to becoming the successor of Hitler?

• What were the Nazi's plan for Hitler's death?

• Since Hitler promised the world a "1000 year Reich" who would have been in line to be the next fuhrer and was there a plan on how it would have been decided?

• Why was Göring chosen to be first in the line of succession? Why did Hitler choose him above all the other potential candidates?

Well considering he didn't commit to a successor until his last will in which he set up his successor government I don't think it was very well planned. Hitler's personality cult put him at the center of Nazism in Germany, so I don't know how much such a thing was talked about. Even after repeated assassination attempts Hitler didn't put a plan into place until February 1945. The Nazis were in power for 9 days after Hitler died, though they didn't have very much real power.

Hitler's noted megalomania also probably limited contingency planning that revolved around his death. However, what really happened is that his power was split three ways. Karl Donitz became the leader the main executor and leader of the armed forces, the Joseph Goebbels because the nominal leader of the legislature but he killed himself the next day so it was passed onto an acting head, and Martin Bormman because leader of the Nazi party. This would have diluted the absolute power he had, but as I said the new government didn't last long so it didn't matter.