Just a suggestion, some of us play daily but occassionally say have weekends away during events. The idea is to allow a fixed time events as currently but instead offer a window of say 3 days in which to start and then have it run as currently.
I think it would be useful too split the time section on expeditions further down, so you can see time required for each part to reach target number for expedition, it would make it easier to see the limiting factor on time till you can do it
 "Crafting Idle Clicker"){kind=icon}
As Pikol13 mentioned, each requirement has a tooltip with the time needed to produce the required products.