Hi, i have also noticed this happening to me today.
However i am changing from bt broadband hopefully tomorrow so it dosn't really bother me. But it is abit strange them changing it.
Hi. I have recently noticed a change in my IP Address with BT Broadband. It is now a 227.44.xxx.xxx rather than 81.156.xx.xxx. Has anyone else noticed this? Help would be grateful for I am unsure on the reason. Have BT done this to all broadband customers in the UK, or just me? Maybe updated my exchange?

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