My numbers may be a little off but when we agreed to a 5-hour ADG at USAir in the late 90’s, our min. credit per day was, I think, only 2? Point being the company immediately, and predictably, exploited it - 4-day trip, work hard the first 3 then one short leg home the last day you got hosed. All the 4-days started paying right around 20 hours; you need a high min. day to go along with ADG.