Hello, Elle!
I do not know what BACS stood for, too!
I see it on a bank statement, though!
I knew the volcano, but "Nore" is new to me.
The mutiny I knew about was at Invergordon.
Do you know that BBC are showing several programmes next week to remember Passchendaele?
There are several events up here about it, too.
Right, this is my clue/problem!
21d, "Fabulous writer of a work about French art?" (5)
A?s?p.
i think it is "Aesop" the fable writer chappie.
But...!
"A" is in clue. work is "op", which leaves "French art" = "es".
Why is French art "es"?
It is not in Chambers.
Anne Bradford has it, but no explanation.