I have 6 zones. Each runs for approximately 30 minutes and the cycle is set to end by sunrise. That means my first 2 zones remain wet for over 3 hrs before the sun comes up. After only one year of usage I had a very unpleasant and unsightly experience: My first 2 zones experienced large patches of bare areas (no grass). I forget what my lawn service called it, but essentially I was either over watering or watering in the evening and the grass was remaining wet over night. Since I don’t believe ~30 minutes is over watering, and since only the first 2 zones were affected, it must be the lawn is wet for too long. PRODUCT SUGGESTION: Sequentially alternate which zone starts first. For my application (6 zones), zone 1 starts first, upon the next cycle zone 2 starts first, next cycle, zone 3, and so on and keep alternating with each cycle. This way, the same zones do not stay wet the longest (and become susceptible to disease).
Where do you live and what type of grass do you have? Have you ever done a catch test to see how much water is being applied in that 30 minutes? It looks like you have a heavier type of soil which has a higher capacity to hold water. I have a sandy soil here in Texas and have never run a station more than 20-25 minutes in the hottest driest part of the summer.