I have a basic water softener control valve question. Maybe someone can clarify this for me.

I have new water softener with a Clack control valve on a 30,000 grain tank. The valve is programmed with a 30,000 grain capacity and a 30 gpg water hardness which displays a 1000 gallon capacity after a regeneration. As I understand, 15 pounds of salt will restore 30,000 grains or 1000 gallons of capacity. But the salt use setting is programmed with 7 pounds per regeneration which is supposed to restore only about 22,000 grains of capacity. It seems that the valve is letting the resin tank remove more grains of hardness than it will restore in the next regeneration. Doesn't this mean that hardness will build up in the resin tank over time?

Shouldn't the valve take this salt setting into consideration when calculating the restored capacity after a regeneration and display that there is only a 733 (=22,000/30) gallon capacity? If not, why?

Should the softener capacity be explicitly programmed to equal the capacity restored by the salt used per regeneration? If not, how is this dealt with?