Field help (IRVADAT) 

Date on which the re-evaluation is saved. This non-modifiable date is automatically entered according to the "Effective date" selected. 
It corresponds either to the start date of the current period, or to the start date of the current FY (if the FY is not divided into periods), or else to the fiscal year end date.
This date is mentioned on the event(s) corresponding to the action of Revaluation.