Just a clarification on the relocations. E84 gets one relocator at a time. The firehouse is only 1.2 miles from the fire, a straight shot down Broadway. At that time of night there shouldn’t be much traffic, so they can make good time. So as each engine left E84, another was called in to replace it. As long as that engine was in quarters, dispatch probably sent them to the scene. IF, the relocator was Engine 90 from the Bronx and they were just leaving their firehouse when the call for an additional engine/s came in, dispatch wouldn’t send them because they aren’t even in E84’s district.
I worked many years as a dispatcher, and it’s difficult to really grasp what is going on out in the field with relocations, other calls going on, travel time, etc. What may be current now is only a snapshot in time. Five minutes from now the situation could be totally different. It’s not easy. It’s not rocket science either, but you really have to be paying attention with your ears for the radio traffic and to the CAD status board to see who is going where and how long ago did they leave.
One point of interest. For extreme large events sometimes a forward staging area may be set up at a firehouse close to the fire with 3 or 4 engines and 2 or 3 ladders because of the rapid deployment of resources at the scene. For the St George Hotel fire in Brooklyn, they used E207/L110 quarters as a forward staging area. Still under the control of dispatch, but close enough where they could get to the fire’s Staging Area quickly.