Will 3.5 be the LTS release for the 3.x series?
From Joomla! Documentation
No. The strategies have been modified to not lock in a specific release as the LTS release of a series. Under the revised strategy, unless superseded with a newer minor release, there will be at least two years of support for the last minor release of a series. The concept of an LTS release is being eliminated in favor of this. For example, if 3.4 were to be the final minor release of the 3.x series, it would be supported for at least two years after its release.