We are traveling to Rio Grande next week for 2 nights and want to visit El Yunque, but the advance reservation tickets were already gone when we planned our trip. I understand a number of tickets are withheld and released 24 hours prior for last-minute travelers, but I've been checking the Recreation.gov website to see how fast they go and they always disappear immediately, making me wonder if there's some sort of robo-reservation thing happening. Anyone have advice for obtaining last-minute tickets to the Road 191 corridor? Or otherwise visiting El Yunque outside the 191? We'd rather not go as part of a tour, but would consider it if that's the only option. Thanks.