The settings dialog allows you to switch timing point during the event, it also manages the locally stored data on your device.
You can force the app to reupload any missing times (which were not previously uploaded) or all data from the event again.
Note that when doing this - the CURRENT time zone of your device will be taken as well as the CURRENT start date in the timing module, this is to allow data to be fixed if your settings are incorrect during the event.
To minimise the storage used on your device you can also delete the data from the database for either the current event or all data (all events).