With the 3dWarp step it is
3dWarp -card2oblique 9518_run_1+orig. -prefix 9518_avg_obl_anat 9518_avg_anat+orig.
followed by
align_epi_anat.py -epi2anat -tshift off -epi_base 0 -skullstrip_opts -no_use_edge -anat 9518_avg_obl_anat+orig -epi 9518_run_1+orig
-child_epi 9518_run_02+orig 9518_run_03+orig 9518_run_04+orig
When I run it without the 3dWarp it is
align_epi_anat.py -epi2anat -tshift off -epi_base 0 -skullstrip_opts -no_use_edge -anat 9518_avg_anat+orig -epi 9518_run_1+orig
-child_epi 9518_run_02+orig 9518_run_03+orig 9518_run_04+orig
I am not sure if it makes a difference but we did clustered acquisition for our datasets, so there is an acquisition, then roughly 10 seconds of off time and then another acquisition.
Thanks for your assistance, if you need anything else let me know.