Even if your boss isn't quite as understanding as Northern Highflyer's, you don't need to lie.
I told my boss I'm doing a CPL. "What - to become an airline pilot?" I laughed: "No, of course not!" Then I told him how I was in the bar at the airfield the other day, when someone mentioned that there was a job going doing a bit of aerial photography on the occasional weekend (which is true, as it happens), and the CPL would put me in a position where I'd be able to do that kind of thing if another opportunity arose, as well as being a challenging and fun thing to do.
FFF
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