It is your responsibility to ensure that your application is completed before the application submission deadline. Otherwise, the selection committee will examine your application based on the information provided, even if there is very little or none at all.
The registration fee is non-refundable in the event that your application is not completed in time. The call for applications runs for a relatively long period (i.e. several months) and an extension of several days beyond May 31 is often granted each year to allow everyone to finish their application without undue stress. The organisation does its utmost to help you submit your application and complete your file under the best possible conditions.
One last tip: don’t wait until the last day to complete your application! Each year, it is total panic for some candidates on the last day even when there has been an extension of a few days. If you experience a technical problem at the last minute, we won’t be able to help!