Moved out, working on GAL

[fightin]

So question following background:

Going to see my SS this week when my W has him and I'll have to keep it to an hour because I double booked myself with a friend. I wasn't originally going to see him on the nights she has him, but I miss him and do want to see him.

IF, and that's a big IF but I want to be prepared, she asks why I need to go so soon how do I handle that? Plan is to just say I have things I need to do, but what if she pries?