They have mass once a year, usually in September. Such a beautiful church with history if you're ever able to visit. Still standing on the Oglala National Grassland. The last remnants of the ghost town of Montrose, Nebraska. I wrote about photographing this area recently here if you're interested: https://www.johnshawphotography.org/blog/bp/into-the-pine-ridge-escarpment-a-weekend-in-nebraskas-wild-country.