For the past few years Mozilla has been on a solid six week cadence for shipping new Firefox releases while for the remainder of the releases in 2016 they are tweaking that schedule slightly.

Firefox releases will now be on a variable six-to-eight week release cycle while still delivering the same number of releases each year. This ensures that there is at least six weeks for every release and the cycles are adjusted for emerging user/market needs.

Firefox 45 is expected on 8 March, Firefox 46 on 19 April, Firefox 47 on 7 June, Firefox 48 on 2 August, Firefox 49 on 13 September, Firefox 50 on 8 November, and Firefox 51 on 24 January of next year.

More details via the Mozilla.org blog.