I agree. The flooding occurred in three major events. The last one was in the 7-8,000 year time frame. Remember that the Black Sea flood is dated at 5,600BC. I think it took that long for the Mediterranean to refill through the opening at Gilbralter and then cascaded into the Black Sea. I suspect the Gulf Of Mexico went through something similar. I have some wood from a forest thats on the bottom of Santa Rosa Sound (Florida) that dates to about 7,000BC.
BTW, the Gulf Of Mexico scenario is pure speculation (I know of no evidence), I came up with that thought as about the only way to explain the underwater structures (if they turn out to be structures) off the coast of Cuba. They were built on the shore of a dessicated Gulf Of Mexico in pre-history. They are one-half mile underwater and that seems like too much for subsidence.