Add the time that a holiday request is submitted

We regularly have employees putting in holiday requests on the same day (for example to leave 30 mins early) which generally isn't an issue if the manager is in, however i am finding more employees are putting in their requests when managers have left (e.g. they are either part time or have booked a half day themselves) and take it upon themselves that it's ok to go! I would like to see the time that the request has been put through so that i can challenge it as i don't get a notification of the request not being their line manager.

Either that or block same day requests...