Next major release of Kamailio is going to be versioned.
The plan to release it was sketched during the last IRC devel meeting back in February, proposing to get it out by beginning of June 2015. Given there has to be at least one month of testing, the next milestones to release date were proposed:
freezing the development: Wednesday, April 22, 2015
if testing goes smooth, then branching 4.3 after about one month: During the week starting May 18
test more in beta phase, prepare packaging, etc. and release after 2-3 weeks: One of the days between June 4 and 11