The Asterisk release cycle is very predictable these days. Approximately every 4-6 weeks we do a release generally on a Thursday. Once a year we do a new major release at AstriCon. Making this predictable for people is something that I, and others, keep in mind all the time as it allows others to plan their own situation better.
As part of the release process we do a release candidate (or multiple) before the full release. This gives a period of time between 1 to 2 weeks for people to test out the release. I highly urge you to test release candidates if possible. This helps both yourself to make sure that the release works in your environment as well as others in the community as a whole. It’s impossible for us to test all variations but by having others test the release candidates we gain greater certainty and confidence with the full release.