SEP is valid in the UK for 24 months on UK/JAR licences so no difference between National Authorities.
Get your examiner to confirm with the UK what they want him to do. This will depend how long your SEP has lapsed.
If it's expired less than 5 years, the CAA will probably want a copy of his examiner authority, ask him to complete a SRG1119, and get him to sign your FCL150 in your licence upon successful completion of the LPC.