New SIM only contract to replace phone contract.

[Bagwan]

If my existing contract runs out on day 10, do I put the new SIM card in on day 10 or day 11?

[Bagwan]

When do you need to insert the new SIM?  So if, for example the existing contract completes on day 10, do you insert the new SIM on day 10 or day 11? 

[bristolian]

There's not usually any need to replace a perfectly working SIM unless there's a fault with it?

Changing from one priceplan to another is just that - a plan change, and should happen automatically on your existing SIM without any action needed from you.

[Bagwan]

Thank you for the reply,  That is what I thought would happen, but I received a message that a new SIM would be sent by 2nd class post,  Maybe that was just a general message that is sent to everyone, but is not relevant if you are an existing EE user?

[bristolian]

Are you sure you've not inadvertently ordered an additional new line, with a new number?

Check on your myEE online account how many lines you have, and whether there's anything unexpected listed.