Welcome Graham.
Not aware of any other courses run local to Chelmsford. You could do distance learning and just take an assessment?
Is it BASC you're worried about or Epping?! (BASC also run a course at Pulborough, not too far out of the way if dates are an issue)
Have you considered a weekend course and staying away (if time in the week is an issue) - check out Jelen Deer Services, who run a course over a weekend.
E t R