bob wrote:

Sorry, yes 2 core and 1 earth.

John just to confirm, I take it doesn't matter if the red/black/earth
earth wires are running back to a switch (Method 1) or a junction box
(Method 3) as this is the supply regardless, correct?

That's right. As the new lights are using the same switches, all you
are effectively doing is replacing one light fitting with another.

I've had a look in the double switch, there are 3 cables entering it,
2 of which run to a pendant and the other I presume is the circuit
cable?

It depends how it is wired.

If you have:

- all the neutral (black) wires are joined together
- all the earth wires are joined together
- the three live (red) wires going to switch terminals
- a wire linking the two the switches

then the cable that is joined to the link wire is the supply, and the
other two cables go directly to the light fittings.

John
--
John White,
Electrical Contractor