Storm Captain?

[Canadane]

But don't hold your breath for them. All the ranks except for First Lieutenant were in the game from launch. They didn't add First Lieutenant until midway through Heavensward - that's more than three years later! There's no telling how long it will be until we get the next rank.

It was more like 6 years later, give or take.
It's been the cap since 1.0.