It is bodgy, put I can guess at the purpose.
My guess?
The third outlet (to the right of the switch) is the aerial down lead.
With the switch turned on, this down lead also feeds back up to the distribution amplifier in the loft for the other rooms. With the switch off, the up link to the distribution amplifier is disconnected, and passed over to the far left outlet, allowing you to introduce a sky box, connecting the RF2 to the far left outlet, putting TV and sky around the home. Not sure what the far right outlet is doing, but suspect it could be the SKY outlet, but with the incorrect module is use (should be an F type).
Purely a guestimate as to the use though.
I thought could the show house have been fitted with cameras to monitor people walking through rooms and was this part of that system?
If you operate that switch, do you loose any TV reception on any of the outlets, or perhaps it just gets worse and drops out?
Trying to use a switch to switch a coax like that would be problematic - The signal can jump gaps with ease.
Whoever fitted it thought they were being clever, but it's quite poor.
Certainly no form of fibre optic or cable TV service.
BT are likely running in fibre for the street cabinets, and if your lucky, to your home. They will offer you "BT Infinity" fibre optic which can just be FTTC - Fibre To The Cabinet. The last final connection from the curb side cabinet to your home will use your existing BT copper cable. (or if you are lucky, they may run you fibre, but it's rare).
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