There are two main changes in the latest version of Part P of the Building Regulations. The first change relates to the range of electrical installation work which requires notification. The range has been reduced, previously work in kitchens and outdoors was notifiable. Under the new regulations, unless the work requires the provision of a new circuit and is not in a special location it will not require notification.
The other major change is regarding the use of a registered third party to certify notifiable work. In the previous edition of the Building Regulations, an electrical contractor carrying out work covered by Part P but not registered with a competent persons scheme was required to notify Local Authority Building Control (LABC). It would then be down to LABC to consider if the proposed works were acceptable under Building Regulations. Under the current edition of Part P, any installers which are not registered with a competent person scheme, are required to get work signed off by a registered third-party.