As noted in the HHVM 4.153 release post, we are moving to releases every other week. The plan detailed in that post had us moving to releasing every 2 weeks starting after HHVM 4.156, but for administrative reasons that was delayed. As a result, this is the first week with no release, and this post is just a reminder of why. The next release (HHVM 4.160) is planned for next week.