You ever seen the Burnside video, P1 change of quarters back in the 80's, first one ever.
It can be done but I doubt it needs to happen often, depends on what fire cover is around.
The MFS training trucks went to the dump fire, so they could free up normal pumps, but from the sounds of u\it, they were running very very thin, I was surprised they didn't instigate more CFS COQ's, or where they told they couldn't have them?