Brad Miller seemed confident that T1 would be gone in 2025.
The initial consultations had the T1 check in being used right through the construction project, but, they now expect all airlines will be long gone from Terminal 1 by the end of the project.
The reason T2 probably doesn't look as big is because MAG are going to be using new, yet Un-patented technologies to assist in check in. This would mean that for the best part, the majority of check in will form as a bag drop function, rather than the queues for seat allocations and so on as now.
I'm just trying to format the PDFs to demonstrate the phases. Might be later this evening.