That could be handy occasionally. Maybe even lock it behind an education or additional feature for donator/subscriber. 

This was raised before and I agree this would be a great improvement. Also, my idea of how it should work:

Should only be able to cancel it when expediting time is still in the first half (while the team is heading to the location) - no point of canceling when the team is heading back from the expedition. 

After cancellation - the return time should be the same as the passed expediting time (team has to come back from the point it was cancelled)

After calling off the expedition, it does not reset - requirements stays the same as it was when the expedition started (not to abuse instead of resetting) 

old but gold

Ah had not spotted this one, would be handy. Upvoted from me.