Not really much is known about him until the early 1840s.

He said a cause of death would not be known until early next week.

Not even his first name was known until last year.

No one had known about the workers until late in the day.

Earth history is well known to us until the 21st century.

The real answer was not known until the 20th century.

Not much is known about the history until the 18th century.

The results will not be known until the third week in May.

The results of the test may not be known until early next week.

But they may not know until next season when he is able to play full time.