Schmitz wrote a popular series of novels and stories about a galactic federation called the Hub. This is the only one of the stories that I’ve read—about Gefty Rammer, the captain of a space freighter that is commissioned by a secretive man named Maulbow who claims to be from a race of future time travelers.
Also, according to Maulbow, there was a race of the future, human in appearance, with machines to sail the current of time through the universe—to run and tack with the winds of time, dipping in and out of the normspace of distant periods and galaxies as they chose.

Variants

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  1. “The Winds of Time” by James H. Schmitz, in Analog, September 1962.
    2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by James H. Schmitz