Early August trip to WWoHP - return tickets?

I am planning a one-day trip to USF and IOA in early August. We only intend to see the Harry Potter attractions at both parks and do not have early entry. I am concerned that if we spend time to see all the Harry Potter attractions at either Diagon Alley or Hogsmeade before taking the Hogwarts Express to the other park, all of the timed entry return tickets for that day will have already been distributed and we will miss out on seeing that park. Should we try to hit the major attractions at both parks first and save our “lingering” for later in the day? Which park should we do first?

Check out the Wizarding World One-Day/Two-Park Plan. It is in two parts because the TP Optimizer can only deal with one park at a time.
http://touringplans.com/plans/1144171
http://touringplans.com/plans/1144177

Timed return is not really used now only at new years/xmas. With 2 wwohp now the crowds are spread out more. Do the tp as suggested ^^