Can I continue work on F1-OPT status while I am waiting for my Green Card (via marriage) employment authorization to arrive?

I am on F1-OPT, my husband is US Citizen. We have been married for over a year but his job and my PhD research meant that we were in and out of US, making it impossible to apply for a green card since I could not meet the Advance Parole stipulation. We are more stably located now & planning to apply for a green card as I will be able to stay in US till I get an AP. But I am unclear about what happens to my OPT based work authorization in the period while I am waiting for the green card EAD to come? Can I continue working in this period or does my OPT work authorization get nullified as soon I apply for a green card? My University's international office is giving information different from INS helpline. We do intend to get an immigration lawyer but I thought I would begin here. Many thanks!