administrative process delay I485

[hugo12345 0]

I am a 22 year old American citizen. I petitioned for my parents to have their green card on June 16, 2016 in san Antonio TX. they have no criminal record or delinquencies and have paid their taxes. they have done everything correctly. my mother gets her residency approved in October (i485) and no answer for my father yet. the priority date as of right now for san Antonio is July 17, 2016. after countless calls to immigration we received no answer and all runarounds. We submitted an INFOPASS on June 12, 2017. the officer told us that my fathers case went through an "administrative process" but that everything came out okay on April 24, 2017. my father then asked the officer what we should do now, which to her response was to just wait. we asked for an ETA which she replied she has no clue and even though the priority date has skipped us, all we can do is just wait.

my questions are

What is an administrative process?

what is the average processing time or waiting period?

and What can I do as a citizen to expedite this process?  

 

THANKS IN ADVANCE FOR THE HELP