Frodo, it seems that you are more knowledgeable than I on these matters, thanks for the info

Thank you.Frodo, it seems that you are more knowledgeable than I on these matters, thanks for the info
They will be the two wires at one end (top or bottom) of the intermediate switch.it’s just a matter of identifying the right switching wires coming from the other switch
The common will be one of the wires (in the same cable as the above two) NOT connected to the intermediate switch.and finding the common going into the intermediate
if I want to abandon one of the 2 way switches and replace the intermediate with a 2 way all the wires will be there it’s just a matter of identifying the right switching wires coming from the other switch and finding the common going into the intermediate

Yes that would be a starter.Has any attempt been made to establish how it's currently wired?
Before offering advice can we have pics of the other 2 switches wiring, clearly indicating which one you wish to keep and which to 'abandon' and do you have any test kit to identify the cables at the intermediate.
Yes that would be a starter...
you don’t have to do anything at the intermediate if you don’t wish to.
Just remove the other switch you want and connect com to one of the other wires
Correct but it may not be the nicest way of doing the job.To do the minimum amount of work, and to avoid "messing things up" all you need to do is go to the switch you wish to remove and join some wires. A photo of this switch would be useful, so we can be sure you will get it right first time.
The intermediate switch can stay as it is.
This will also avoid buying switches, trying to match existing switches, etc.
Unfortunately all this has come about as we are swapping the switch style from white plastic to G&H antique brass, they don’t do an intermediate in the style we want. The lounge has 3 switches for the light, a 2 gang ( 2 way) at one entrance, a 2 gang (with intermediate) at the bottom of the stairs and a 3 gang ( 2 way) at another entrance, we don’t use the switch in the 3 gang so I’m looking to do away with that. The house is 2 yrs old so wiring is up to date.To do the minimum amount of work, and to avoid "messing things up" all you need to do is go to the switch you wish to remove and join some wires. A photo of this switch would be useful, so we can be sure you will get it right first time.
The intermediate switch can stay as it is.
This will also avoid buying switches, trying to match existing switches, etc.
However, they do make Intermediate Switches and fit them to Wall-Plates of several antique brass styles.Unfortunately all this has come about as we are swapping the switch style from white plastic to G&H antique brass, they don’t do an intermediate in the style we want.
They do have grid switches in the rangeUnfortunately all this has come about as we are swapping the switch style from white plastic to G&H antique brass, they don’t do an intermediate in the style we want. The lounge has 3 switches for the light, a 2 gang ( 2 way) at one entrance, a 2 gang (with intermediate) at the bottom of the stairs and a 3 gang ( 2 way) at another entrance, we don’t use the switch in the 3 gang so I’m looking to do away with that. The house is 2 yrs old so wiring is up to date.
I will take photos of the rear of the other 2 switches to help but because of the switch style options I will have to swap the intermediate for a 2 way
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