Does anyone know what the air raid type alarm is going off for? I think it is Bootle Docks area.

I just heard it, checked google and in 2008 someone asked the same and it's to signal shift change at he docks

10 minutes after I put this thread up, it stopped. However it has been going for hours.

Well that's not a shift change then is it?

Erm - no.

Would of helped if I'd actually written what I was mean too after the ?
I was going to say I have no idea what the sound was then, as I only heard it for a short period of time. I was unaware of the fact it had been going on for hours.