I just applied and am waiting to get results of the drug test and background check, I selected night hours, but I want to switch to days before I'm hired, can I call to switch or do I need to show up in person and ask?

Once you Esign the acceptance letter you will have to work the shift for 90 days till you are able to do shift change which they do almost every 4 months

You have to work the shift and department you were given for 90 days before you can request a change.

I don't can't help

Not really sure. Things change from day to day with Amazon. Ask the agency you applied through, or the Amazon HR dept.

When I was there I was told if you wanted to switch your times you would have to withdraw your application and reapply. All of that was done at the recruiting center or the temporary agency where they did all the hiring. However the process may have changed since September of last year and you might be able to talk to somebody without having to withdraw and reapply.