The website lists only one source?
The Encyclopedia of Tanks and Armored Fighting Vehicles - The Comprehensive Guide to Over 900 Armored Fighting Vehicles From 1915 to the Present Day, General Editor: Christopher F. Foss, 2002
I’ve got 40+ books on the Panther and there’s no proof that any where completed
I’ve seen Panther F hulls on assembly lines mixed with Panther Gs and wooden mock ups but no evidence of Panther Fs that were completed
I can’t be arsed to go into date and numbers of changes so ill let Peridexion do that, I’m sure he already has
But if you want to model a Panther F, Panther 2, Maus, E100 or IS-3 fighting in or around Berlin, it entirely up to you