Surface Pressure (sea level pressure in hectopascals (hPa) ) forecasts...

[SennenCove-UK]

The  DataPoint API documentation suggests that the  datapoint:   val/wxfcs/all/datatype/locationId   returns, amongst other things,  a  P value in the  SiteRep object.

P  float or int Mean sea level pressure in hectopascals (hPa)  

When I make my call, I get most of the other  Rep  data items but no 'P'

Any ideas why ?

Tnx.