The Marr Plan Action Team will hold a rally at the BLM Rock Springs Field Office, 280 US Highway 191 in Rock Springs, WY, according to a story posted today by Wyo4News.
Although indicated when the Decision Record was signed in July, the incident does not appear in the latest schedule.
Western Horse Watchers was unable to find a web site for the Marr Plan Action Team.
Western Horse Watchers Association 
You might find some info here: MARR-PLAN for Wild Horses
https://www.facebook.com/groups/547211602563477/