ASDA Night-Shift Stocker interview questions

I filled in an application form and dropped it back in January, I got a call in JUNE! As it was initially for a 2nd job I agreed to attend the selection evening. This was a room full of around 20 people where we had to do standard "team building" exercises. At the end of the selection evening the manager conducting the meet asked if anyone wanted to work that night! As in directly after the group selection. Some of the people said yes and were offered contracts there and then. Others like myself were called back as "reserves" The group selection was at 8pm on a Friday night finishing around 9.30pm. The shift the manager wanted people to work was from 10pm that night to 6am the following morning. There was meant to be a 2nd personal one to one interview and a 2 hour trial shift they call Best Welcome. I did not have either of those prior to being offered my regular shifts.