Script Assertion checking dateTime

I am new to SoapUI, and have a question about a script assertion I need to put together. I have a DB DateTime in UTC value that I need to check against. So basically I have

def SQL_Departure = context.expand( ' ${yada_yada.Segment#ResponseAsXml#//Results[1]//resultSet[1]/row[1]//Departure[1]}; ).replace(".000000 ", "")

With the assert, I need to ensure that the table is not getting populated with records with a departure datetime less than 96 hours, so somewhat like:

assert SQL_Departure >= getUTCDate() + 4 //or 96 for hours instead of 4 for days. Would anyone know the best way of going about this? 

Thanks,

Steve