I just noticed in TeamWin FAQ, if I get the' No OS Installed' message that I would need to restore the system partition.
which I do not have and if I did I can't restore anyways because it was done with the older version of TWRP.
You can use a current version of TWRP to restore a backup created with an older version. I've done it... recently... as in last week. I used 3.0.2-0 to restore a backup created over a year ago with 2.8.1.0. No issues.