Individual Data Files are limited to 255 elements, so the controller can only have N7:0 through N7:254, and F8:0 through F8:254.
But you can define many additional data files. The first 8 data files with the traditional data types (B3, T4, C5, N7, F8, etc) are automatically created with just one element each when you create a new project.
These data files are expanded automatically when you use a new address from them.
But you can create many additional data files. I'm not certain of the limit.
So you can have N10, N12, F18, F22... anything you like.