We’ve released a first (and likely the only) release candidate for Wt and JWt 3.3.9. The Wt 3.3.9 release mostly adds features that were previously only available in Wt 4, like the Microsoft SQL Server backend for Wt::Dbo. The JWt release merely consists of bug fixes.
Here are the links for 3.3.9 RC 1:
Binary builds for Windows are available on the GitHub releases page.