Generally, when planning our ADRs we have discussed multiple options and have settled on the one we want. If it comes time to book the ADRs and the one we want is not available, I already know what our second option was and go straight for it, but I don't write it down anywhere.
We booked our ADRs a few months back and didn't have any trouble getting what we wanted. We are still making some small changes now and aren't having troubles finding what we want. But we're also not going during a busy time of the year.