In the manual, you note
We generally estimate the bias field based on the mean b=0 image, and apply the estimated field to all DWI volumes.
From my understanding I could use the dwibiascorrect script
dwibiascorrect input output [ options ]
In this situation, as input I would input the mean b=0 image, and then use the -bias flag to get the estimated field in the output.
How then could I apply the estimated field to the rest of the diffusion series?