How can i upgrade to Prometheus from Frontier directly from Internet?
With the type of release model Netrunner Standard Edition (Kubuntu) uses, going from one release to another a re-install has always been the recommended path to use. Please keep in mind that Netrunner 14 is an LTS (long term support) release with 5 years of security and bug fix updates, Netrunner 15 is a standard release and is only supported for 6 months.
There is no upgrade path due to the many fundamental changes that come with Plasma 5.2