SBAS interferogams

Hi everyone. Could someone clarify whether I need to back-geocode multiple times in order to create an SBAS that includes all possible IFGs or if there is a less time consuming way? I plan to export geocoded binary data (i.e. yyyymmdd_yyyymmdd.disp.geo.bin) data to an external SBAS software other than StaMPs. Since the back-geocoding/ESD step only creates one output file used by the interferogram, it would seem that this step has to be performed N(N-1)/2 times in order to generate the set of all potential interferograms needed for SBAS and that there would be (N-1) masters in essence? Since these masters are geocoded, could I use the geocordinates tile in the subsets in order to match up pixels to different ground areas.

My Processing flow is currently BG/ESD->IFG->Deburst->GWFilter->Subset->Unw->PHase to Displacement -> Terrain Correction

Would I need to move the terrain correction up in the flow (like below) in order to make these pixels line up better?

BG/ESD->IFG->Deburst->GWFilter->Terrain Correction->Subset->Unw->PHase to Displacement

I am using Sergey Samsonov’s SBAS program as Matlab is too expensive for me at the moment.

Thank you so much for your advice.
Robert