After applying and completing "personality test" online, I received an invitation to attend the group hiring event (interview). Now, I believe you have to complete a video interview before being invited to the hiring event.
You are responsible for your own transportation to the hiring event. There, you, along with 100-400 other applicants, go through several rounds of the interview. First, they check to make sure you have all the required documentation, of which you are made aware well before the event. Then you all sit through a presentation about the company and the position (it's actually pretty entertaining).
Then all the applicants are broken up into two groups, which are dealt with independently by separate hiring staff. There are some personality type activities and smaller group activities to test how you work with others as well as your speaking presence/customer service aptitude.
They are watching you and your attitude through the ENTIRETY of the interview (from the time you're waiting in the morning before checkin to the very end). Stay POSITIVE, hold up a GOOD ATTITUDE, and be aware of your presence and the company you keep.
They make a couple cuts of applicants (the first is very big, about half; the second also significant, but not as great). Then they give you a lunch break.
When you return, all the remaining applicants gather together again for another presentation. After this time, the hiring staff checks that all applicants satisfy the physical requirements (i.e. you lift a full carry-on suitcase above your head). Then they interview you face-to-face (two interviewers to every applicant).
After the face-to-face, they send you out of the interview room, and you wait in another room until you hear the result. While you wait, you fill out some minimal info on a computer with one of the hiring staff. Then they bring you out of the waiting room to finally let you know if you're hired (provisionally, of course) or being let go.
If they decide to hire you, you immediately go into another room (where they have coffee/refreshments for you; it's really quite a long day by the time you make it to this phase), where you fill out some new hire paperwork and take your badge photo (Ladies and Gents, make sure it's a good one, because you are S-T-U-C-K with it for good). Then you get drug tested on site.
You will hear back from the company pretty soon afterwards regarding your employment status and plans for Initial Training.
Good Luck!