Bermuda won't work there leaving St Augustine and fescue as the two logical choices. The fescue might work in Irvine, but St Aug would be a slam dunk. I would visit with the people at Roger's Gardens and get their opinion(s). My problem with fescue is the watering requirements in a state with an ongoing water crisis. When a lawn is planted in the area for which it is well adapted, it will take an inch of water per week in a 90-degree summer month. When you bring a cool season grass like fescue to the south, the water required to keep it alive goes up. You might be watering it 3x per week.