The BLM manages 248.3 million acres of public land, more than any other agency, according to a March 2017 report by the Congressional Research Service.Among other things, this will save the BLM travel money. Regional managers won't have to go cross-country to reach "the flagpole" as HQ is sometimes called.
Aside #1, this is old military jargon, as the flagpole on a base or fort is in front of the commandant's office. Aside #2, BLM in the press in the last 3-4 years more often referred to Black Lives Matter. This sounds odd to long-time westerners who are accustomed to, if not always happy about, the Bureau of Land Management in their communities across the West.