You can figure out what tags were "leftover" by looking at draw odds reports. If an area has more tags than applicants listed, then there were tags left over. I am guessing you main options for elk in Wyoming will be reduced price cow tags, and lots of them in some areas. Many of them never sell out. A good portion of them are late season tags that will focus on winter range areas. Your best bet at hunting a bull this year is to do over the counter in Colorado. You will fight the crowds but elk can and will be harvested on these hunts. If I were in your shoes, I would try to get a cow tag for the area you want to hunt next year for a bull. You can treat it like a scouting trip with the benefit of still getting to hunt!