You can dialate a couple of inches n stay at that for weeks b4 you actually go into Labour. If they allowed you to go back home you r fine just be patient til it's time.
My due date is July 20th as well. I've heard it happening to others as well, but they went into labor a couple weeks after. The good news is that you are so far along that the chance of complications are very slim. I wish you the best of luck!