Word Choice

Two things:

What is the purpose of "that I uploaded" in this sentence?

Attached is another fully executed sub-agreement that's ready to be interfaced.

I also don't understand "that's ready to be interfaced."

If it's "fully executed" (whatever that means), doesn't that imply it's ready to be interfaced?

"That I uploaded" and "that's ready to be interfaced" are interoffice phrases. I wanted advise on whether "that's ready" or "and it's ready" was the better choice, but made that as unclear as my two example sentences! Lol Thanks Mame!