It is frustrating. We found several would only post a month to 6 weeks in advance. It made it very difficult. There are few colleges who offer anything on Sundays, we did not realize that when we started planning. The timing makes it impossible to get to more than 2 full info sessions and tours in a day, even when they are right by each other.
Also, check for parent weekends, etc…those become tough on some campuses or hotels.
When booking flights, airlines do not think it will get much better in the fall, plan for late flights and extra travel time. Flying into one airport and leaving from another can help so you do not need to circle back.
Safe travels.