This is how you get round the upgrade issue. If you only have F.O. time don't tell them. Tell them you were a Captain before, they don't check and the interview process is easy for expats. Just join as a Captain even if you are not, you will get through the Captain sims as they are easy, its been done before. Once they knowingly took a Float Plane Pilot and put him left seat 737, it helped that he knew one of the management pilots.
However its best to be honest and not do this.