FTextureSource.GetMipData() won't retrieve Mips other than 0


           TArray<uint8> rawData;
			uint32 texSizeX = landscapeTextures[l]->Source.GetSizeX()/ (Mip + 1);
			uint32 texSizeY = landscapeTextures[l]->Source.GetSizeY()/ (Mip + 1);    			
			uint32 arraysize = landscapeTextures[l]->Source.GetBytesPerPixel() * (texSizeX*texSizeY);
			landscapeTextures[l]->Source.GetMipData(rawData, Mip);
			for (int c = 0; c < rawData.Num(); c+=4)
				//rawdata is BGRA
				FColor color = FColor(rawData[c + 2], rawData[c + 1], rawData[c], rawData[c + 3]);

This code will return proper colors when the Mip variable is 0. Any other value for the Mip level will return 0 for all bytes in the rawData array.

I know I initialize it with AddZeroed, but the array still isn’t getting filled with any byte values from the GetMipData function when Mip>0.

I even commented out that Mip bias snippet from the texSizeX and Y lines. Still nothing. Bug?