STC and HMC order

Hi

I do have 1 question about STC and HMC processing order.

Now I know that fMRIprep preform STC before HMC.

It removes non-steady-state volume using AFNI’s 3dTshift.

Let’s say I have 103 volumes total.

If I use --dummy-scan 3, I use 100 volumes during STC right?

when I preform HMC, which images I used to estimate BOLD reference image?

Removed 3 volumes by AFNI’s 3dTshift? or other images in 100 volumes?

It would really appreciated to have clear answers.

Thanks

Junyong Oh.