Bertha skips a previously announced rest break and keeps digging the Highway 99 tunnel route as it enters downtown Seattle.

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Bertha has broken new ground this week by running in beast mode instead of taking a previously announced four-day break just inland of the Alaskan Way Viaduct.

The 57-foot-wide tunnel machine had been scheduled to pause early Tuesday, to rest the crew and undergo maintenance after 11 days of 24-hour digging, Seattle Tunnel Partners (STP) project manager Chris Dixon announced Monday.

Instead, Dixon’s team called an audible, and kept pushing beyond the announced 385-foot point that concluded the treacherous phase below the fragile viaduct.

STP wanted “to reach a better location for the machine to stop,” said Laura Newborn, spokeswoman for the Washington State Department of Transportation. She did not have details about where and when the stop will occur, or why that location is preferred.

During the viaduct phase, state officials closed the elevated highway to traffic from April 29 until Sunday evening, by which time Bertha had covered 312 of those 385 feet, with no evidence of damage to the viaduct.

The machine has been advancing faster than expected, making roughly 40 feet of progress per day in what Dixon has called firm, consistent soil.

In all, Bertha has completed more than 1,945 feet of the 9,270-foot route from Sodo to South Lake Union, where the future Highway 99 tunnel could open by spring 2018.