Changing an Old Plug Socket - New socket has 2 earth terminals

The two earth terminals are linked so either one will be ok. And you don’t have to take an Earth to the metal backbox anymore.

That’s no problem there linked anyway just leave other earth screwed down

The two earth terminal are internally linked. Personally I use one for the CPC off the cables and the other to Earth the metal back box. However this isn’t required now but I still do it as it is good practice. Hope this helps

If it’s a metal back box then unsure that is looped in too. But yes you can just use the one as they are interconnected.

A double skt front with two earth terminals is called a high integrity skt more computer based. Either earth terminal is suitable as both earth terminals are linked however I would still run another earth link to the metal back box for if skt front was to be removed and no earth link to metal back box leaves the potential for back box to become live if skt front were to be removed.

All new double socket outlets have 2 earth terminals so that if the circuit is wired in a ring the earth connections can go separately.

yes

New double socket outlets have the earth terminal inter connected, so either earth terminal on the socket will be fine to connect to.

As DEACON ELECTRICAL SERVICES said, however, it is good practice to take a ‘fly lead’ essentially just another CPC (green and yellow cable) from on of the two earth terminals- without going too in-depth, the copper is more conductive material than the screws so in the event of a fault it will trip faster though this won’t be significantly noticeable as it will be like 0.01 of a second, also with time and methods of installation I have noticed that some of these galvanised back boxes can start to degrade and being that the screws are your earth path for your back box this isn’t ideal. Though seemingly far fetched, it’s good practice none the less so would recommend it