Well, Lynne, for me the last two weekends in Oct were free from festivals this year but I accept that Oct can get a bit chilly for those camping!
If you had arranged it for Sept or early Oct this year you would have clashed with (among others!):-
4 Sept - Wareham Wail / Wallingford Bunkfest / Fylde FF
11 Sept - Bromyard FF / Swanage FF / Great Yarmouth MF
18 Sept - Otley FF
25 Sept - Whittlebury Song&Ale / Concertinas at Whitney
2 Oct - Black Dog Pennymoor Song&Ale
9 Oct - Banbury FF
You are likely to clash with something therefore. So at the risk of stating the obvious, perhaps its best to clash so with a Festival in another part of the country rather than a Song&Ale close by!
Good luck in sorting out a date and venue!
I agree with Kitty, fix it asap and give an early booking discount!
"But give me a boat...!"
Alan