You are not required to open an online registration in Athletics.app, where one can register in advance. Although it does save work for the organization during post-registration.
During post-registration, ask for athletes' license numbers as much as possible, if you enter the license number in Athletics.app all data will be completed automatically. Of course, (post-)registration without license number is also possible.
You can keep the online registration open until you need your first jury form. To print jury forms you need to go to 'Stage 2' in Athletics.app and from that stage the online registration will automatically close. Please note that online registration closes for the entire competition, not just the first event.
See also this related question about post-registrations in Phase 2:
https://www.athletics.app/faq/?qa=278/atleten-invoeren-wedstrijd-serie-begonnen-achteraf-toevoegen
This has been automatically translated into English