PrimeNG LTS has been announced last week as an annual subscription based service to provide a license for the finest compatible version suited to you. LTS covers the prior two versions from the latest release, this means up to 18 months of almost weekly releases to bring the latest defect fixes and security updates to your project. As an example, when PrimeNG moves to Angular 9, PrimeNG 7 and 8 will move to LTS support whereas STS (short term support) versions of PrimeNG 9 will be open source under MIT license for at least 6 months until PrimeNG 10 is released. Here is a timeline to visualize the LTS support.
If you are not planning to migrate to Angular 9 and PrimeNG 9 yet, we strongly suggest LTS versions to receive weekly performance, security and quality enhancements as PrimeNG 7.x and 8.x are in active development.
Please visit the official announcement for changelog and more information;