After the D Concourse and North Processor construction is complete then the D Widening project will start. This will enlarge the main terminal building between the C and D Piers so that thw 4 gates there can be used for domestic or trans-border flights.
After that will be the East Terminal Expansion. This will see the east end of the main terminal building (by the A Pier) bumped out about 15 meters.
This is only new construction and doesn't address the ongoing renovation projects within the building.