Correct time delay between transducers

Hi everyone,
I would like to do a timereverse simulation. Indeed I have a point targeted by multiple SEFT that are going through different part of the skull. I would like to calculate the phase delay to be able to be at the focused point with all my transducers at the same time.
To do so I tried to do it manually by adding a source at the focus point and receptors (that are the transducers). It kind of work but then it is a real struggle to calculate precisely the phase. I did that following the instruction in the paper from Kyriakou et al. : Fullwave acoustic and thermal modeling of transcranial ultrasound propagation and investigation of skullinduced aberration correction techniques: a feasability study.
Is there any other easier solution to calculate this delay?
Thanks

What do you mean with 'it is a real struggle' to calculate the phase? I used a python script for this. Would this be an acceptable solution?
The idea is this (all in Python):
Have a list of points indicating the coordinates of the base of the tranducer (can also be automated via Python)
Interpolate the field values (complex values) of the reverse simulation at these points
Calculate the phase of the complex value and conjugate it
Create new simulation and add these phase values to the different sources of the transducer