US Postal Service Holiday Clerk Assistant interview questions

I applied on October 27th I got an email on November 4th to interview on November 9th. It was it was an individual interview but there was a lot of people interviewing. She explained I would basically be sorting mail and asked would I be able to come in to work early like between 2 and 3 am. On December 5th I received 3 emails saying congratulations you got the job you have 7 days to accept or decline, you have 2 days to fill out this online information for your background check, and you have 3 days to got take a drug test. I did all of that the next day and I didn't get an email from them until December 23 telling me my orientation/ first day of work will be December 27th. This was confusing because the holiday season was basically over. After orientation they couldn't get through to the office I was supposed to work at so I went up to the place the next day because I couldn't get through either. The manager called me later that day and said I start at 4 am. It turned out that I would be working at the Annex and not the store.