Is it better to send the letter or email Greenwich Council? Should one do both?

The Tudor Barn is a great building and should be kept open, and used by the people of Greenwich. Rarely does one find such a large room, such a welcoming place. Folk Mob is by far the largest and best attended Folk Club in the S.E. London Area.Recent reports have 52 singers attending on one night. The wakes for Brixton Bert and Dave Bryant would have been difficult to hold anywhere else, due to the sheer number of performers, friends and relatives that attended.
What would prevent the Folk Mob from "Bringing Their Own?"