1 inch of water on 5000 sq ft of landscape per week over the month is 25 HCF.
The poster has a 4000 SF house (two-story) on a 9000 sf lot, halve the house and add 50% for garage and driveway, you ‘ve got 3000 SF of house footprint. 6000SF of land.
if they went from 4 or 6 minutes every other day to 6 or 8 minutes, that’s an even bigger jump. i.e. 50% or 33% respectively.
Minutes don’t matter, flow rate matters. Because flowrate controls water lay down and coverage.