To my knowledge, the Panther was designed to eventually replace the Pz.IV, but failed to be produced in high enough numbers to do so. However, I've had difficulty properly sourcing this claim when contradicted. I'm curious if anyone here knows any good source to put an end to any debates about the intent. Thanks in advance.
In his interrogation by the CIOS (Evaluation Report No.153, 28 June 1945), Stiele von Heydekampf states that:
"The PzKw IV was scheduled to go out of production in mid year of 1945 and the program for the production of the PzKw III/IV was dropped in the fall of 1944. All facilities freed by these cancellations were to be devoted to the production of the 38-D. The 38-T was to be built in limited numbers with a lighter hull for use as a recon vehicle."
There were also production projections given for mid-1945:
38-T/38-D: 2000 units per month
Panther: 300 units per month
Jagdpanther: 150 units per month
Tiger II: 150 units per month
Jagdtiger: 50 units per month
More precise production projections obtained by Soviet intelligence give more detail. Production of the PzIV is winding down and was scheduled to cease in May. Production of the StuG IV would also cease. Curiously, the Jagdpanzer IV would remain in production for some time longer.