Can [Cu(NH3)2]^+ and/or [Cu(NH3)3]^+ be oxidised by air to become [Cu(NH3)2]^2+ and [Cu(NH3)3]^2+ respectively?

The Cu+ ion is relatively easily oxidized by air but since the coordination number of Cu is 4, it would add two more molecules to make [Cu(NH3)2(X)2]+2. If in water solution the X probably would be H2O molecules, if in ammonia solution it would form the [Cu(NH3)4]+2 ion.