Yes, it is a perpetual license for that major version. If the author releases Tsreader 3.0 (hypothetically), older licenses may require an upgrade fee, but minor updates (e.g., 2.8.5 to 2.8.6) are free.
For readers who decide to stick with the official version, here is a quick installation guide: Tsreader -FULL Version- download
Before searching for a "full version" crack, it is crucial to understand that Tsreader officially exists in two forms: Yes, it is a perpetual license for that major version