Suppose you were sent home earlier from a gig. In that case, this is still considered a 'cancellation of the gig' after the cancellation period has expired. This means you are still entitled to 100% of the agreed hours. If the client cancels the gig before the gig starts, you can claim 50% of the agreed hours. 

Suppose the client cancelled the gig in the app. In that case, you will automatically receive a notification allowing you to claim the hours. In case they send you home earlier, clearly state in the comment section why you have entered 100% of the total hours when submitting your hours.