This value I'm getting through Connect SQL which is storing in specified TempPage in clipboard,however policydate field is specified as varchar(20) in sql server from where this value is getting fetched using connect sql.
value 18010 is not a valid Date or DateTime string. Details: Invalid value for theDate passed to RUF-addToDateYM.addToDate(String, String, String, String, String)
Seems like there's no available function in PRPC to convert a date string to GMT. So you might need to create a custom function which would do the GMT conversion. Below code could be taken as a reference. But this one's just sample for a format mm/dd/yyyy or m/dd/yyyy
//Format accepted : mm/dd/yyyy or m/dd/yyyy
String GMT = **dateinput**;
String  array = GMT.split("/");
//adding a zero to handle single digit date or month