Question re $core_v2_activityStory and sort order of date

Hi 

I have a query re the sort by option for the activity story stream, we have an issue where updates/replies are not appearing at the top of the list and noticed that the stock widget is sorting by 'Date'

#set ($query = "%{ SortBy = 'Date', SortOrder = 'Descending', PageSize = $pageSize }")

But the documentation says 

SortBy String Sort mechanism. Option 'Date' is obsolete. Optional LastUpdatedDate CreatedDate, Date, LastUpdatedDate, StoryIdsOrder



Can you please confirm which value we should be using, I am assuming that 'Date' is still valid as its being used in the stock widget but would be good to get confirmation and any advice