The Future with Present Continuous
Introduction:

In English there are 4 ways to express the future.
Compare:
I will leave tomorrow – using will (future simple)
I am going to leave tomorrow – using going to (same as will)
I am leaving tomorrow - using the present continuous (scheduled)
I leave tomorrow – using the present simple (scheduled)
These forms are the result of many years of the living language of English. There is no logic.

Structure:

We are looking at the present continuous for the future.
(It must be a scheduled event)
Subject + am/are/is + verb (ing) Subject + am/are/is + not + verb (ing) Am/Are/Is + Subject + verb (ing)

Examples:

I am meeting the client at 2pm.
You are not meeting the client tomorrow.
I'm not meeting the client at the meeting later.
Are you meeting the client at the show?
Isn’t he meeting the client?
Aren’t they meeting the client soon?