How often are rates updated and at what time?
Rates for accounting purposes in ERP applications are generally loaded daily or less frequently. There is no need, or ability, to load rates more frequently than daily.
OANDA market rates are updated once per day at midnight Universal Time.
Xignite market rates are updated every hour, so you can choose a ‘fix time’ to use according to what time of day you want to load the rates.
Central bank rates are generally updated daily, at different times depending on the bank.