Admin side: Ability to set a first deadline

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Atm its just done event.date - 1.month, which is ok and does the trick, but ideally we d want the proper date that the admin can select as a first deadline date.
Also as part of this, there it should be displayed next to the user, as we ll have some users accepted on the first deadline and some on the final deadline. As an admin I would like to have ability to see that on the event admin page.