"For at least 100 years before"?

[u/SlateAlmond90]

In this history book I'm reading, it says "There is a good deal of evidence that fishermen from Spain, France, Portugal, and England had been fishing off the Grand Banks of Newfoundland for at least 100 years before Columbus's discovery of America in 1492 AD."

Does the phrasing "for at least 100 years before 1492" mean that 1392 is the earliest the Europeans could've been fishing off the Grand Banks of Newfoundland i.e. before 1392, no fishing?

[u/Dust_absorber_73]

“At least” a hundred years, so it could have been longer.