She was pulled up to 100mph i think. Which means she accelerated from 100 to 184 under pedal power (with assistance from the air cushion). And of course she made it as easy as possible (which still lies in the realm of stupidly difficult) to do it - the record is simply about going as fast as is possible pedaling a bike.
When the commentator says 157, she is still tethered.
The tether is released at 163.
I reckon she was pulled until 160 miles per hour.