[joekiser]

From http://www.mtier.org/news/openbsd-ports-lt-support/:

Customers who sign up for LTS subscription service for example for the current v5.3 release will automatically receive free support for the first six months and then an additional 6 month's support until v5.5 is released. Remember that OpenBSD stable is currently 6 months only. The subscription model will include only security and stability updates and no functional updates of packages. For those customers who have a need for functional updates then please contact M:Tier directly.