Saw on another forum that if you upgrade to version 4.x and write a tune, then absentmindedly use an old laptop with v3.x to read that same tune back in, your interface will get tamper locked or something and no longer work. Is that true? I am on V3xx still because I haven't had a need to upgrade, and am considering never upgrading if there is a poison pill that may kill my interface later. If this is true why does this happen?