I'm pretty sure you're misinterpreting that. Sublime text 3 isn't even out of beta. Here's the response I once got asking a question about the Sublime Text 4 upgrade fee.

" Thanks for your email.

The license you buy now is a version 3 license, even though the production version of 3 has not yet been launched. This license will work on version 2, 3 whilst in beta as well as on the production version of 3.

Major version releases will come with an upgrade fee; we expect major versions to be released every 18-24 months, so you are not looking at upgrading for at least two years.

We haven't built our pricing structure for upgrades from 3 to 4 as yet, but please use the policy we have to upgrade from 2 to 3 as a guide:

    Upgrades from Sublime Text 2 to Sublime Text 3 will become available when version 3.0 is released later this year. Until such time, upgrading is not required, as Sublime Text 3 will accept Sublime Text 2 license keys during the beta period.
    For customers who purchased in the 90 days prior to the announcement of Sublime Text 3, we are reducing the cost of upgrading from $15 down to $11. Customers who purchased Sublime Text 2 before this time period are still subject to a $30 upgrade fee when 3.0 is released.

"