Nature and recording of Standby Duty
 

I have asked the UK CAA on three occasions recently and am still awaiting an answer, am I surprised, not at all!
My job requires a large amount of daytime standby duty. My on-site manager seemingly has no idea of how standby is to be recorded. To keep it simple as I understand it you should be told (on the day prior to a standby duty) the start and end time and the nature of the standby duty to be undertaken. By nature I understand this to be location of and if it is to be a standby from home if it is to be counted at 50%. Without wanting to go into too many details on how incorrectly he reads the FTL requirement I believe that if the standby duty is to be recorded at 50% then you should be advised of this when notified of the period of standby, not applied at the end of the standby duty period.
Is this correct?