The times can over lap. When you get the first fast pass it will tell you what time to come back. It gives you an hour window of time to return. it will also have a time when you can get the next fast pass. This time will usually be 5 minutes or so after the earliest time you can use the first fast pass. So, if you don't use the first one at the earliest possible moment, you can go get a second one and then have 2. The second one will also have a time when you can get the next one.