SaveCustomDataTable behaviour in different Versions of OS

I have used SaveCustomDataTable in OS v9.01 where you need to clear the data before loading the table and it works fine.

Recently i was building similar logic in OS v8.2 and noticed that it was truncating my table , is this expected or is there something i am missing

it is the standard call:
BRApi.Database.SaveCustomDataTable(si, "Application",Table,dt,True)