It seems like there should be a concise term meaning a temporary base of operations. The implication would be that it's where someone has established a transient headquarters in an area they do not intend to be long-term. Scientists may have a dig site, soldiers a temporary command center, a business traveler a hotel, explorers a base camp. What is a generic phrase for this? I'm assuming there's something more concise than "temporary base camp."
Although it's more of a camp or a shelter than a headquarters, you could use bivouac.
bivouac (n) - A temporary camp without tents or cover, used especially by soldiers or mountaineers.