Altering reaction stoichiometry results in a change in oxidation state distribution in bis-calix [4]arene supported [Mn10] cages, without significantly altering structural topology. DFT calculations reveal that the shift in oxidation state levels from [Mn III 6Mn in compound 4 to [Mn III 4Mn in compound 3 results in a significant decrease in the magnitude of some antiferromagnetic exchange contributions, a switch from ferromagnetic to antiferromagnetic in others, and the loss of significant spin frustration. Indeed, the change in oxidation state from Mn III -Mn III to Mn II -Mn II in the central J1 interaction causes a 10-fold change in the magnitude of the exchange interaction.