A registration deadline sets the last day players can sign up for a part. That gives you enough time to build the schedule and assign the courts. You set the deadline per part, so each part (each division) of an event can have its own deadline.
How the deadline works
The registration deadline is a date, not a time. Players can sign up through the end of the deadline day. So if you set the deadline to 18 July, registration stays open all that day and only closes after midnight. There is no option to pick a specific time of day.
If you leave the field empty, the start date of the part acts as the natural deadline. Players can then still sign up on the start day itself.
Once the deadline has passed, the sign-up button on the public page disappears automatically and players see a message that registration is closed. The same rule applies behind the scenes: the registration API rejects a late sign-up, even if someone still has the link. So the display and the security always reach the same verdict.
