Reserve question:

I'm trying to drop one day of reserve next month. Can't swap reserve days so am trying to figure out whether to use a "Personal Drop" or "Authorized Personal Drop." I know it's been covered before but can't find it on the search. I've never used either one before so any guidance would be appreciated. Also, the contract (sec 23.I) is kinda confusing me.

The day I'm trying to drop is the last day of the month of October. Thanks for the help.