Insar pair Export Gamma slave header problem

Dear all,

After do coregistration for a pair (or a stack) InSAR, I exported it to Gamma format. I want to have start_time and end_time of each image to calculate with orbit.
However, I found SNAP only generate Master parameter file and not Slave files.
I tried also with GPT stampsexport operator but there was no Slave parameters information.

Is this a s1toolbox problem or I miss something ?
How can I extract start_time and end_time for each slaves in a coregistrated stack ?

Thank you in advance.


I attached a couple of parameter files to better understand the problem. 20150624.rslc.par (7.2 KB) 20160724.rslc.par (7.2 KB) 20170225.rslc.par (7.2 KB) 20170625.rslc.par (7.2 KB)