So, I introduce several ideas to make it easier to manage. In this case, the idea should be simple to do. It consists on adding 3 columns in the list of presentation for a schedule :
1- duration of each presentation
2- total duration starting from the first presentation in the list. I mean, show the total duration of the schedule since the start of (for instance, for the 3rd presentation, total duration would be duration of presentation 1 + duration of presentation 2 + duration of presentation 3)
3- Show the planned timeline for each presentation (specific schedule for each page).
If you feel interesting, please like it ;-)