PERM application processing time

Hi, my company HR answered the DOL questionnaire and the PERM was officially filed on Apr 16, 2018 (I understand this to be filing the ETA-9089 form to apply for the PERM). What is the current timeline in my case? My current H1-B visa expires Dec 5th 2018 (6 years + captured time outside country). Do we have to wait until the PERM is approved to apply for H1-B extension? What will my options be if my PERM is not approved by mid October?

In the case of my wife, the PERM process lasted exactly 4 months (Aug 24, 2017 - Dec 23, 2017).