And, of course, if you buy the download from TTX, any later downloads of the full installation file that you might make....those contain all of the most recent updates, so it is no longer the initial "beta" file that is issued in Nov-Dec. I downloaded the full installation file for the 6th time just a few days ago. I don't expect to need them, but I might get a new computer and would use a new installation .exe file to install there.
(don't know if 3rd party sellers use fully updated installation files if downloaded later)
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
