Originally Posted by
fairviewroad
So was T4 still in operation when T5 opened? Why didn't they just call the new international terminal T4?
T4 is reserved for when/if they develop an additional terminal. It would apparently sit on the site of the current power/steam plant, which would be moved elsewhere. This would put it between T3 and T5, so using T4 makes sense.
On a related note - why does T1 have Concourse B and C, but not A??
There also is no Concourse I, but I've always assumed that was to prevent confusion between J and I.