Questions about the expansion of space:
If space is discrete and described by unchanging constants that determine the Planck length, what does it mean for space to expand?

Does this mean that units of space are added as space expands?

If space expansion is not due to the addition of spatial units, then do particles/waves/fields have some sort of built-in repulsive force on very large scales?

Or is this something not answerable without a theory of quantum gravity?