Theory: Renji is a Future Captain when Captain Byakuya Dies/Retires from Position

Renji is being mocked by some people as "Forever Lieutenant" despite having Powers in the same stratosphere of a Mid Tier Captain.

But I think somewhere, sometime in the Future,

Renji will be a Captain.

Especially, when Byakuya dies or retires from his position.

Though, it wil be a very long time. As Byakuya is very difficult to Kill. And too workaholic to resign.

But when that time comes,

I think Renji will become a Captain.

What do u think?