generally, you should be entitled to some ingress and egress easement. the easement should be the least intrusive as possible. In otherwords, you may be able to pick the most convenient. the public policy here is that society should not have wasted land due to land locks
most likely you will have more than 30 days
depending on your state law, you should have a lot more time than you think. chances are that they will have to file a law suit and you may even have a chance to petition the judge for more time.