The FG organization had close links to the wardens service, as they operate over the same area.
If a fire takes hold & gets beyond the FG they go to the wardens post to get assistance from the NFS.
So if you can find out where the wardens post was, that would be a good start.
thats a good point Aaron the plot thickens ,another bit of research unbeknownst to me was the war time operation rooms under dover castle
thanks very much for the extra info austro ,you've been a great help