Hi,

It's difficult when you have the situation you described.

If this were me, I would size the softener to work best for the 80-90% of the time - not the 10-20% when it's at max capacity.

It will be a balancing act - I would size it so that when it's just two people, there's a small amount of salt waste because instead of usage triggered regen, the Day Override is forcing a regen. At max capacity it might be doing a usage based regen every couple days.

I would target a regen interval of 14 days as the max (Day Override) - yes, 26 days is too long