Air Gateway NorCAL Rights? Denying Request?

[chucky2night]

Question. I work at a airport hub here in northern California and requested to leave early only Monday and Wed like 30 min for the upcoming dates Jan 2015 to May 2015 because I need to take a class for school. Supervisor said No but I know that at this same facility others in the past were able to do so. Is there anything written that I can take to help my case?
I am part-time package handler at airport hub.
Thank you

 

[silenze]

Ask your mom to write you a note so you can leave early

 

[UpstateNYUPSer(Ret)]

Allowing others to leave early establishes a past practice which you can use when you file the grievance over not being allowed to leave early.