Even if you were a user of such an early version as 2.x, you would get a new license key for free by e-mailing Mr Ghisler. So, even though the license does not mention the word "lifetime", in essence it is a lifetime license (until further notiice )
Yes, it's a lifetime license. The disclaimer "until further notice" is there for cases which we cannot control. For example, if a new function which is essential for TC to run requires a per user patent license, it would not be possible to offer a free update for everyone. But hopefully this will never happen...