Just to be clear, 'familiarisation' does not have to be 'delivered' by anyone. It may be sufficient simply to read the flight manual or POH for the aircraft to be flown although, in the case of the less experienced pilot, some additional guidance may be appropriate. Once completed, there is no regulatory requirement for any recurrent differences training or familiarisation and neither requires any form of test or check (although the owner/operator may have specific, non-regulatory requirements in this regard). An SEP class rating proficiency check is valid for any SEP aeroplane on which differences training or familiarisation has ever been completed.