Does it mean trouble for the unfiled tax returns that date way back?
It is in fact very much complicated if your unfiled tax returns trace to at least six years backwards. It is so because the files are kept in storage and it will need enough concerted effort to locate those records. An agent will need to browse through all of the kept files to be able to gather them all. You can just imagine how difficult it could be if your unfiled tax returns date back to some more years back in time.