you are right that in all other cases pay is based on 40 hours but the rate mentioned on SOC is based on 39 hours. so if your COS says 40hrs a week then pay should be calculated based on that
Rate calculated on 40 hrs for 2134 (experienced rate)
(40,600/39)*40 = 41,641.05
SOC recent (look at page-5 which mention that all rates are basedo n 39hrs. I know its confusing)
https://www.gov.uk/government/uploads/s ... l_2015.pdf
The rates are based on a 39-hour working week for all occupations where the salary source used is the Annual Survey of Hours and Earnings.
Where other salary sources are used, please note that the rates are based on the following weekly hours:
Where the source is NHS Agenda for Change or the Royal Institute of British Architects, a 37.5- hour week;
Where the source is teachers’ national pay scales, the definition of a full-time teacher is used when determining those pay scales;
Where the source is the National Grid submission to the Migration Advisory Committee, a 37- hour week;
In all other cases, a 40-hour week.