Nope... can't say I've ever tested how long an output can sink or source current continuously. But then.... what does continuously really mean? Hours, days, years? I did dig through the same data sheet again, and didn't see any charts relating to this. Sounds like what you want is some endurance test data. Maybe one of the 'ol pros can give you some information based on some of their applications. Sorry I could'nt be any more help.