In which cases can maintenance be performed on a temporary fire base?

If an organization wants to carry out maintenance on temporary fire bases and it is not a case of AOG or occasional maintenance, that is, if you want to make use of fixed facilities (warehouse, office, etc.) and it is estimated that the use will be greater than 40 days, you must request the opening of a line station for each location.  
Otherwise, support could be provided by a mechanic on board / traveling in a van if the need to request opening of installation (although defining in the EOM the necessary procedures).